KR20220107076A - Light-emitting device, electronic device, and lighting device - Google Patents

Abstract

A light emitting device, an electronic device, or a lighting device having low power consumption and high reliability is provided. The light emitting device includes a first light emitting element, a second light emitting element, a third light emitting element, and a fourth light emitting element. The first to fourth light emitting elements include the same EL layer between the anode and the cathode. The EL layer includes a first light emitting layer and a second light emitting layer. The first light emitting layer contains a fluorescent material. The peak wavelength of the emission spectrum of the fluorescent substance in the toluene solution of the fluorescent substance is 440 nm to 460 nm, preferably 440 nm to 455 nm. The second light emitting layer contains a phosphorescent material. The first light emitting element exhibits blue light emission. The second light emitting element exhibits green light emission. The third light emitting element exhibits red light emission. The fourth light emitting element exhibits yellow light emission.

Description

Light-emitting devices, electronic devices, and lighting devices {LIGHT-EMITTING DEVICE, ELECTRONIC DEVICE, AND LIGHTING DEVICE}

The present invention relates to an article, method, or method of making. The invention also relates to a process, machine, manufacture, or composition of matter. In particular, one embodiment of the present invention relates to a light emitting element, a light emitting device, an electronic device, a lighting device, a driving method thereof, or a manufacturing method thereof.

A light emitting device using an organic compound as a light emitting body, which has characteristics such as thin shape, light weight, high speed response, and DC driving at low voltage, is expected to be applied to next-generation flat panel displays. In particular, the light emitting device in which the light emitting elements are arranged in a matrix is considered to have an advantage in that it has a wider viewing angle and superior visibility than a conventional liquid crystal display device.

The light emitting mechanism of the light emitting element is known as follows: when a voltage is applied between a pair of electrodes interposed between an EL layer including a light emitting body, electrons injected from the cathode and holes injected from the anode are transferred to the EL layer They recombine at the luminescent center of , to form molecular excitons, and when the molecular excitons return to the ground state, energy is released and light is emitted. Singlet excitation and triplet excitation are known as excited states, and it is thought that light emission can be obtained through either of these excited states.

In order to improve the characteristics of the light emitting device containing such a light emitting element, improvement of element structure, material development, etc. are actively performed (for example, refer patent document 1).

Japanese Laid-Open Patent Application No. 2010-182699

In the development of a light emitting device, a reduction in a driving voltage or a reduction in the amount of current is one of the important factors for achieving low power consumption of a product. In addition to the device structure in which the carrier balance in the EL layer of the light emitting device can be controlled or the recombination probability of carriers can be improved, the light emitting characteristic of the light emitting layer in the EL layer is an important factor for reducing the driving voltage or current amount of the light emitting device. to be. Therefore, it is important to reduce the amount of driving voltage or current of a light emitting device having a light emitting layer having improved light emitting characteristics by using an EL layer having a desired structure. It is preferable that the light emitting element has a lower driving voltage and higher reliability.

In view of this, one embodiment of the present invention provides a light emitting device, an electronic device, or a lighting device with low power consumption. Another aspect of the present invention provides a light emitting device, an electronic device, or a lighting device with low power consumption and high reliability. Another aspect of the present invention provides a novel light emitting device and a novel light emitting device. In addition, the description of these subjects does not interfere with the existence of other subjects. It is not necessary to solve all the problems in one aspect of this invention. Other subjects will become apparent and can be extracted from the description of the specification, drawings, and claims and the like.

One embodiment of the present invention is a light-emitting device including a first light-emitting element, a second light-emitting element, a third light-emitting element, and a fourth light-emitting element. The first light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The second light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The third light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The fourth light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The first EL layer includes a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element. include The second EL layer comprises a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element. include The charge generating layer includes a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element do. The charge generating layer is between the first EL layer and the second EL layer. The first EL layer contains an organic compound in which two benzo[ b ]naphtho[1,2- d ]furanylamine skeletons are each independently bonded to a pyrene skeleton. The second EL layer has a function of emitting phosphorescence. The first light emitting element has a function of emitting blue light. The second light emitting element has a function of emitting green light. The third light emitting element has a function of emitting red light.

Another embodiment of the present invention is a light-emitting device including a first light-emitting element, a second light-emitting element, a third light-emitting element, and a fourth light-emitting element. The first light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The second light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The third light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The fourth light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The first light emitting element includes an anode. The first EL layer is between the anode and the charge generating layer. The first EL layer includes a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element. include The second EL layer comprises a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element. include The charge generating layer includes a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element do. The charge generating layer is between the first EL layer and the second EL layer. The first EL layer contains an organic compound in which two benzo[ b ]naphtho[1,2- d ]furanylamine skeletons are each independently bonded to a pyrene skeleton. The second EL layer has a function of emitting phosphorescence. The first light emitting element has a function of emitting blue light. The second light emitting element has a function of emitting green light. The third light emitting element has a function of emitting red light.

Another embodiment of the present invention is a light-emitting device including a first light-emitting element, a second light-emitting element, a third light-emitting element, and a fourth light-emitting element. The first light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The second light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The third light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The fourth light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The first light emitting element includes an anode. The first EL layer is between the anode and the charge generating layer. The first EL layer includes a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element. include The second EL layer comprises a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element. include The charge generating layer includes a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element do. The charge generating layer is between the first EL layer and the second EL layer. The first EL layer contains an organic compound in which two benzo[ b ]naphtho[1,2- d ]furanylamine skeletons are each independently bonded to a pyrene skeleton. The second EL layer has a function of emitting yellow phosphorescence. The first light emitting element has a function of emitting blue light. The second light emitting element has a function of emitting green light. The third light emitting element has a function of emitting red light.

In the light emitting device having any of the structures described above, the two benzo[ b ]naphtho[1,2- d ]furanylamine skeletons are bonded to the 1-position and the 6-position of the pyrene skeleton, respectively.

In the light emitting device having any of the structures described above, the nitrogen atoms of the two benzo[ b ]naphtho[1,2- d ]furanylamine skeletons are each independently benzo[ b ]naphtho[1,2- d ]furan It is bound to the 6th or 8th position of the diary.

Another embodiment of the present invention is a light-emitting device including a first light-emitting element, a second light-emitting element, a third light-emitting element, and a fourth light-emitting element. The first light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The second light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The third light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The fourth light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The first light emitting element includes an anode. The first EL layer is between the anode and the charge generating layer. The first EL layer includes a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element. include The second EL layer comprises a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element. include The charge generating layer includes a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element do. The charge generating layer is between the first EL layer and the second EL layer. The first EL layer contains a first organic compound represented by the general formula (G1), and a second organic compound. The second EL layer has a function of emitting yellow phosphorescence. The first light emitting element has a function of emitting blue light. The second light emitting element has a function of emitting green light. The third light emitting element has a function of emitting red light.

In the general formula (G1), Ar ¹ and Ar ² each independently represent a substituted or unsubstituted aryl group having 6 to 13 carbon atoms to form a ring, R ¹ to R ⁸ , R ¹⁰ to R ¹⁸ , and R ²⁰ to R ²⁸ are each independently hydrogen, a substituted or unsubstituted C 1 to C 6 alkyl group, a substituted or unsubstituted C 1 to C 6 alkoxy group, a cyano group, halogen, a substituted or unsubstituted C 1 to a haloalkyl group or a substituted or unsubstituted aryl group having 6 to 10 carbon atoms.

Another embodiment of the present invention is a light-emitting device including a first light-emitting element, a second light-emitting element, a third light-emitting element, and a fourth light-emitting element. The first light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The second light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The third light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The fourth light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The first light emitting element includes an anode. The first EL layer is between the anode and the charge generating layer. The first EL layer includes a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element. include The second EL layer comprises a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element. include The charge generating layer includes a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element do. The charge generating layer is between the first EL layer and the second EL layer. The first EL layer contains a first organic compound represented by the general formula (G2), and a second organic compound. The second EL layer has a function of emitting yellow phosphorescence. The first light emitting element has a function of emitting blue light. The second light emitting element has a function of emitting green light. The third light emitting element has a function of emitting red light.

In the general formula (G2), R ¹ to R ⁸ and R ²⁹ to R ³⁸ are each independently hydrogen, a substituted or unsubstituted C 1 to C 6 alkyl group, or a substituted or unsubstituted C 1 to C 6 alkoxy group , a cyano group, halogen, a substituted or unsubstituted haloalkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 10 carbon atoms.

Another embodiment of the present invention is a light-emitting device including a first light-emitting element, a second light-emitting element, a third light-emitting element, and a fourth light-emitting element. The first light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The second light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The third light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The fourth light emitting element includes a first EL layer, a second EL layer, and a charge generating layer. The first light emitting element includes an anode. The first EL layer is between the anode and the charge generating layer. The first EL layer includes a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element. include The second EL layer comprises a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element. include The charge generating layer includes a region functioning as a part of the first light emitting element, a region functioning as a part of the second light emitting element, a region functioning as a part of the third light emitting element, and a region functioning as a part of the fourth light emitting element do. The charge generating layer is between the first EL layer and the second EL layer. The first EL layer contains a first organic compound represented by the structural formula (132), and a second organic compound. The second EL layer has a function of emitting yellow phosphorescence. The first light emitting element has a function of emitting blue light. The second light emitting element has a function of emitting green light. The third light emitting element has a function of emitting red light.

Another embodiment of the present invention is a light-emitting device including a first light-emitting element, a second light-emitting element, a third light-emitting element, and a fourth light-emitting element. The first light-emitting element, the second light-emitting element, the third light-emitting element, and the fourth light-emitting element include the same EL layer between the anode and the cathode. The EL layer includes a first light emitting layer and a second light emitting layer. The first light emitting layer contains a fluorescent material. The peak wavelength of the emission spectrum of the fluorescent substance in the toluene solution of the fluorescent substance is 440 nm to 460 nm, preferably 440 nm to 455 nm. The second light emitting layer contains a phosphorescent material. The first light emitting element exhibits blue light emission. The second light emitting element exhibits green light emission. The third light emitting element exhibits red light emission. The fourth light emitting element exhibits yellow light emission.

Another embodiment of the present invention is a light-emitting device including a first light-emitting element, a second light-emitting element, a third light-emitting element, and a fourth light-emitting element. The first light emitting element, the second light emitting element, the third light emitting element, and the fourth light emitting element include the same first EL layer and the same second EL layer between the anode and the cathode, with the same charge generating layer interposed therebetween. . The first EL layer includes a first light emitting layer. The second EL layer includes a second light emitting layer. The first light emitting layer contains a fluorescent material. The peak wavelength of the emission spectrum of the fluorescent substance in the toluene solution of the fluorescent substance is 440 nm to 460 nm, preferably 440 nm to 455 nm. The second light emitting layer contains a phosphorescent material. The first light emitting element exhibits blue light emission. The second light emitting element exhibits green light emission. The third light emitting element exhibits red light emission. The fourth light emitting element exhibits yellow light emission.

Another embodiment of the present invention is a light emitting device having a half maximum width of an emission spectrum of 20 nm or more and 50 nm or less.

Another embodiment of the present invention is a light emitting device in which the x coordinate of the first light emitting element in the xy chromaticity diagram is 0.13 or more and 0.17 or less, and the y coordinate is 0.03 or more and 0.08 or less. Preferably, the y -coordinate of the first light emitting element in the xy chromaticity diagram is 0.03 or more and 0.07 or less.

Another embodiment of the present invention is a light emitting device in which light emitted from the first light emitting element is emitted to the outside of the light emitting device through a blue color filter.

In another embodiment of the present invention, when light having an x -coordinate of 0.313 and a y -coordinate of 0.329 in the xy chromaticity diagram is obtained with a luminance of 300 cd/m ² , the power consumption of the light emitting device excluding the power consumption of the driving FET (first to fourth The total power consumption of the light emitting elements) is 1 mW/cm ² or more and 7 mW/cm ² or less.

In another embodiment of the present invention, when light having an x coordinate of 0.313 and a y coordinate of 0.329 in the xy chromaticity diagram is obtained with a luminance of 300 cd/m ² , the power consumption of the light emitting device including the power consumption of the driving FET (consumption current and The power consumption calculated from the product of the voltage between the anode and the cathode) is 2mW/cm ² or more and 15mW/cm ² or less.

Another embodiment of the present invention is an electronic device including the light emitting device and a connection terminal or an operation key.

One embodiment of the present invention provides, in addition to a light emitting device including a light emitting element, the light emitting element or an electronic device including the light emitting device (specifically, the light emitting element or the light emitting device, and a connection terminal or operation key comprising: electronic device) and a lighting device including the light emitting device or the light emitting device (specifically, a lighting device including the light emitting device or the light emitting device and a housing) are included in its category. Therefore, in this specification, the light emitting device refers to an image display device or a light source (eg, a lighting device). In addition, the light emitting device includes a module in which the light emitting device is connected to a connector such as a flexible printed circuit (FPC) or a tape carrier package (TCP), a module provided with a printed wiring board at the end of the TCP, and a chip on glass (COG) method to the light emitting device. Included in that category are modules on which an integrated circuit (IC) is directly mounted.

According to one embodiment of the present invention, it is possible to provide a novel light emitting device, a new electronic device, and a novel lighting device, respectively. In addition, it is possible to provide a light emitting device, an electronic device, and a lighting device with low power consumption, respectively. In addition, it is possible to provide a light emitting device, an electronic device, and a lighting device with low power consumption and high reliability, respectively. Also, the description of these effects does not preclude the existence of other effects. One embodiment of the present invention does not need to realize all the effects described above. Other effects will become apparent and can be extracted from the description of the specification, drawings, and claims and the like.

1 (A) and (B) show a light emitting device, respectively.
2 shows a light emitting mechanism of a light emitting device.
3 shows a light emitting mechanism of a light emitting device.
4 shows a light emitting mechanism of a light emitting device.
5 shows a light emitting device.
6A and 6B show a light emitting device.
(A), (B), (C), (D), (D'-1), and (D'-2) of FIG. 7 illustrate an electronic device.
8A to 8C illustrate electronic devices.
9 shows a lighting device.
10 shows a light emitting device.
11(A) and (B) show an example of the touch panel of the embodiment.
12A and 12B show examples of the touch panel of the embodiment.
13(A) and (B) show an example of the touch panel of the embodiment.
14A and 14B are block diagrams and timing charts of the touch sensor.
15 is a circuit diagram of a touch sensor.
16 shows luminance-current density characteristics of light emitting devices 1 to 3;
17 shows current efficiency-luminance characteristics of light emitting devices 1 to 3;
18 shows luminance-voltage characteristics of light emitting devices 1 to 3;
19 shows current-voltage characteristics of light emitting devices 1 to 3;
20 shows chromaticity coordinates of light emitting devices 1 to 3;
21 shows luminance-current density characteristics of Comparative Light-emitting Devices 1 to 3;
22 shows current efficiency-luminance characteristics of Comparative Light-emitting Devices 1 to 3;
23 shows luminance-voltage characteristics of Comparative Light-Emitting Devices 1 to 3;
24 shows current-voltage characteristics of Comparative Light-emitting Devices 1 to 3;
25 shows chromaticity coordinates of comparative light emitting devices 1 to 3;
26 shows the emission spectrum of 1,6BnfAPrn-03 in toluene solution of 1,6BnfAPrn-03.
27 shows the structure of a light emitting device.
28 shows the luminance-current density characteristics of the light emitting devices 4 to 7;
29 shows current efficiency-luminance characteristics of light emitting devices 4 to 7;
30 shows the luminance-voltage characteristics of the light emitting devices 4 to 7;
31 shows current-voltage characteristics of light emitting devices 4 to 7;
32 shows chromaticity coordinates of light emitting devices 4 to 7;
33 shows luminance-current density characteristics of comparative light emitting devices 4 to 6;
34 shows current efficiency-luminance characteristics of comparative light emitting devices 4 to 6;
35 shows luminance-voltage characteristics of comparative light emitting devices 4 to 6;
36 shows current-voltage characteristics of comparative light emitting devices 4 to 6;
Fig. 37 shows the light emitting device of the embodiment.
38 shows a comparison of power consumption.
39 shows the luminance-current density characteristics of the light emitting devices 8 and 9. FIG.
40 shows current efficiency-luminance characteristics of light emitting devices 8 and 9. FIG.
41 shows the luminance-voltage characteristics of the light emitting devices 8 and 9. FIG.
42 shows current-voltage characteristics of light emitting devices 8 and 9. FIG.
43 shows emission spectra of light emitting devices 8 and 9. FIG.
44 shows normalized luminance-time dependence characteristics of light emitting devices 8 and 9. FIG.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail below with reference to the drawings. However, the present invention is not limited to the following description, and various changes and modifications may be made without departing from the spirit and scope of the present invention. Therefore, this invention is limited to description of the following embodiment and is not interpreted.

In addition, the terms 'film' and 'layer' may be interchanged with each other depending on the case or situation. For example, the term 'conductive film' may be used instead of the term 'conductive layer', and the term 'insulating layer' may be used instead of the term 'insulating film'.

(Embodiment 1)

In the light emitting device according to one embodiment of the present invention, a light emitting element in which an EL layer including a light emitting layer is provided between a pair of electrodes is used. Various structures can be employed for the light emitting element, for example, a structure in which one EL layer is provided between a pair of electrodes (single structure) or a structure in which a plurality of EL layers are stacked with a charge generating layer interposed (tandem structure) can be employed As an example of the element structure of the light emitting element, a light emitting element having a tandem structure including two EL layers will be described below with reference to FIG. 1A .

The light emitting element shown in Fig. 1A has a structure in which two EL layers 103a and 103b each including a light emitting layer are provided between a pair of electrodes (first electrode 101 and second electrode 102). have In the EL layer 103a, a hole injection layer 104a, a hole transport layer 105a, a light emitting layer 106a, an electron transport layer 107a, an electron injection layer 108a, and the like are sequentially stacked on the first electrode 101. has been In the EL layer 103b, a hole injection layer 104b, a hole transport layer 105b, a light emitting layer 106b, an electron transport layer 107b, an electron injection layer 108b, and the like are sequentially stacked on the first electrode 101. has been A charge generating layer 109 is provided between the EL layer 103a and the EL layer 103b.

The light emitting layers 106a and 106b each contain a plurality of materials such as a light emitting material in an appropriate combination, and can emit fluorescence or phosphorescence of a desired luminous color. Further, on the light emitting layer 106a or 106b, a light emitting layer containing a light emitting material different from that of the light emitting layer 106a or 106b may be further provided.

The charge generating layer 109 injects electrons into one of the EL layers 103a or 103b when a voltage is applied between the first electrode 101 and the second electrode 102, and injects electrons into the other of the EL layers ( It has a function of injecting holes into 103b or 103a). Accordingly, in FIG. 1A , when a voltage is applied so that the potential of the first electrode 101 becomes higher than the potential of the second electrode 102, the charge generation layer 109 transfers electrons to the EL layer 103a. and injecting holes into the EL layer 103b.

In addition, with respect to light extraction efficiency, it is preferable that the charge generation layer 109 has light transmittance with respect to visible light (specifically, the visible light transmittance of the charge generation layer 109 is 40% or more). The charge generating layer 109 functions even if the conductivity is lower than that of the first electrode 101 or the second electrode 102 .

In the light emitting element shown in Fig. 1A, the light emitted in all directions from the light emitting layers 106a and 106b included in the EL layers 103a and 103b is the first that functions as a microscopic optical resonator (microcavity). It can be resonated by the electrode (reflective electrode) 101 and the second electrode (semi-transmissive/semi-reflective electrode) 102 . Light is emitted through the second electrode 102 . The first electrode 101 is a reflective electrode and has a laminated structure of a reflective conductive material and a transparent conductive material. The optical adjustment is performed by controlling the thickness of the transparent conductive film. The optical adjustment may be performed by controlling the thickness of the hole injection layer 104a included in the EL layer 103a.

As described above, by performing optical adjustment by controlling the thickness of the first electrode 101 or the hole injection layer 104a, the spectrum of a plurality of monochromatic rays obtained from the light emitting layers 106a and 106b can be narrowed, and color purity can achieve high luminescence.

In the light emitting element shown in Fig. 1A, an optical path between the second electrode 102 functioning as a transflective/semireflective electrode and the light emitting region of the EL layer 103b closest to the second electrode 102 The length is preferably less than λ/4, where λ is the wavelength of light emitted from the light emitting region. Here, the light emitting region means a region where holes and electrons are recombine. With this structure, standard white light can be obtained by combining a plurality of monochromatic rays from the light emitting layers 106a and 106b of the light emitting element shown in Fig. 1A. The light emitting layers 106a and 106b may include, for example, blue light (eg, having an emission spectrum peak in a range of 400 nm to 480 nm, preferably in a range of 450 nm to 470 nm), green light (eg, 500 nm). having an emission spectrum peak in the range of to 560 nm, preferably in the range of 520 nm to 555 nm), red light (e.g., having an emission spectrum peak in the range of 580 nm to 680 nm, preferably 600 nm to 620 nm) , orange light (eg, having an emission spectrum peak in the range of 580 nm to 610 nm, preferably in the range of 600 nm to 610 nm), or yellow light (eg in the range of 555 nm to 590 nm, preferably 570 nm has an emission spectrum peak in the range of to 580 nm). Further, specific combinations 106a/106b of the emission colors of the light-emitting layers 106a and 106b include those described below: blue/green, blue/yellow, blue/red, green/blue, green/yellow, green/red. , red/blue, red/green, and red/yellow.

Next, a specific example of manufacturing the above-described light emitting device will be described.

Since the first electrode 101 is a reflective electrode, it is formed using a reflective conductive material, and has a visible light reflectance of 40% or more and 100% or less, preferably 70% or more and 100% or less, and a resistivity of 1×10 ⁻² . Use membranes of Ωcm or less. The second electrode 102 is formed using a reflective conductive material and a transmissive conductive material, and has a visible light reflectance of 20% or more and 80% or less, preferably 40% or more and 70% or less, and a resistivity of 1×10 ⁻ Use membranes of ² Ωcm or less.

The optical path length between the first electrode 101 and the second electrode 102 is adjusted for each wavelength of the desired light so that the light of the desired wavelength from the light emitting layers 106a and 106b can resonate and be enhanced. Specifically, the thickness of the transparent conductive film used for a part of the first electrode 101 is changed so that the distance between the electrodes is m λ/2 ( m is a natural number) (where λ is the desired wavelength of light).

In addition, in order to intensify light of a desired wavelength, the optical path length between the first electrode 101 and the light emitting layers 106a and 106b emitting light of a desired wavelength is adjusted. Specifically, by changing the thickness of the transparent conductive film that can be used for a part of the first electrode 101 or the thickness of the organic film forming the hole injection layer 104a, the optical path length is (2 m '+1)λ/4 ( m ' is a natural number) (where λ is the desired wavelength of light).

In this case, the optical path length between the first electrode 101 and the second electrode 102 is strictly expressed as the total thickness from the reflective region of the first electrode 101 to the reflective region of the second electrode 102 . do. However, since it is difficult to accurately determine the reflective regions of the first electrode 101 and the second electrode 102, no matter where the reflective regions are set for the first electrode 101 and the second electrode 102, the It is assumed that the effect can be sufficiently obtained. In addition, the optical path length between the first electrode 101 and the light emitting layer which emits the desired light is strictly the optical path length between the reflective region of the first electrode 101 and the light emitting region of the light emitting layer which emits the desired light. However, since the reflective region of the first electrode 101 and the emitting region of the light emitting layer emitting the desired light are difficult to find out precisely, the reflective region and the light emitting region are located where the first electrode 101 and the light emitting layer emitting the desired light are located. Even if it is set, it is assumed that the above-mentioned effect can fully be acquired.

For the first electrode 101 and the second electrode 102 , any one of a metal, an alloy, an electrically conductive compound, a mixture thereof, and the like can be appropriately used. Specific examples include indium-tin oxide (indium tin oxide), indium-tin oxide containing silicon or silicon oxide, indium-zinc oxide (indium zinc oxide), indium oxide containing tungsten oxide and zinc oxide, gold ( Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), and titanium (Ti). In addition, elements belonging to Group 1 or 2 of the periodic table, for example, alkali metals such as lithium (Li) or cesium (Cs), alkaline earth metals such as calcium (Ca) or strontium (Sr), magnesium (Mg), such as Alloys containing elements (MgAg, AlLi), rare earth metals such as europium (Eu) or ytterbium (Yb), alloys containing these elements, graphene, and the like can be used. The first electrode 101 and the second electrode 102 can be formed, for example, by sputtering or vapor deposition (including vacuum vapor deposition).

The hole injection layers 104a and 104b inject holes into the light emitting layers 106a and 106b through the hole transport layers 105a and 105b having high hole transport properties, and include molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, or oxide. It can be formed using an acceptor material, such as manganese. Alternatively, the hole injection layers 104a and 104b may include a phthalocyanine-based compound such as phthalocyanine (abbreviation: H ₂ Pc) or copper phthalocyanine (abbreviation: CuPc), 4,4'-bis[ N -(4-diphenylaminophenyl) -N -phenylamino]biphenyl (abbreviation: DPAB) or N , N' -bis{4-[bis(3-methylphenyl)amino]phenyl} -N , N' -di Aromatic amine compounds such as phenyl-(1,1'-biphenyl)-4,4'-diamine (abbreviation: DNTPD), 7,7,8,8-tetracyano-2,3,5,6- tetrafluoroquinodimethane (abbreviation: F ₄ -TCNQ), chloranyl, or 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaaza A compound containing an electron withdrawing group (halogen or cyano group), such as triphenylene (abbreviation: HAT-CN), or poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonic acid) (abbreviation: PEDOT/PSS) and the like can be used to form an organic acceptor material.

The hole injection layers 104a and 104b may contain a hole transport material and an acceptor material. When the hole injection layers 104a and 104b contain a hole transport material and an acceptor material, electrons are extracted from the hole transport material by the acceptor material to generate holes, and the light emitting layer 106a is passed through the hole transport layers 105a and 105b. and 106b) are injected with holes. The hole transporting layers 105a and 105b are formed using a hole transporting material.

Specific examples of the hole transport material used for the hole injection layers 104a and 104b and the hole transport layers 105a and 105b include 4,4'-bis[ N- (1-naphthyl) -N -phenylamino]biphenyl (abbreviation: NPB or α-NPD), N , N' -bis(3-methylphenyl) -N , N' -diphenyl-[1,1'-biphenyl]-4,4'-diamine (abbreviation: TPD), 4,4',4''-tris(carbazol-9-yl)triphenylamine (abbreviation: TCTA), 4,4',4''-tris( N , N -diphenylamino)tri Phenylamine (abbreviation: TDATA), 4,4′,4′-tris[ N- (3-methylphenyl) -N -phenylamino]triphenylamine (abbreviation: MTDATA), and 4,4′-bis[ N Aromatic amine compounds, such as -(spiro-9,9'-bifluoren-2-yl) -N -phenylamino]biphenyl (abbreviation: BSPB); 3-[ N- (9-phenylcarbazol-3-yl) -N -phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1); 3,6-bis[ N- (9-phenylcarbazol-3-yl) -N -phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2); and 3-[ N- (1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviated as PCzPCN1 ). Other examples include 4,4′-di( N -carbazolyl)biphenyl (abbreviated CBP), 1,3,5-tris[4-( N -carbazolyl)phenyl]benzene (abbreviated TCPB), and 9 and carbazole derivatives such as -[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazole (abbreviation: CzPA ). The materials listed here are mainly materials with hole mobility of 10 ^-6 cm ² /Vs or more. In addition, any substance other than the substances enumerated herein may be used as long as the hole transporting property is higher than the electron transporting property.

Other examples include poly( N -vinylcarbazole) (abbreviated PVK), poly(4-vinyltriphenylamine) (abbreviated PVTPA), poly[ N- (4-{ N '-[4-(4-) diphenylamino)phenyl]phenyl- N' -phenylamino}phenyl)methacrylamide] (abbreviation: PTPDMA), and poly[ N , N' -bis(4-butylphenyl) -N , N' -bis(phenyl) ) benzidine] (abbreviation: Poly-TPD) and the like.

Examples of the acceptor material used for the hole injection layers 105a and 105b include the above-described acceptor material and organic acceptor material. Among them, it is preferable to use an oxide of a metal belonging to any of Groups 4 to 8 of the periodic table, and particularly preferably to use molybdenum oxide.

The light emitting layers 106a and 106b each contain a light emitting material. Each of the light-emitting layers 106a and 106b contains, in addition to the light-emitting material, an electron transporting material and/or a hole-transporting material that are organic compounds, and in the light-emitting device according to one embodiment of the present invention, one of the light-emitting layers 106a and 106b A fluorescent substance having a peak wavelength of 440 nm to 460 nm, preferably 440 nm to 455 nm in the emission spectrum of the fluorescent substance in a toluene solution, or two benzo[ b ]naphtho[1,2- d ]furanylamine skeletons It contains an organic compound bonded to a pyrene skeleton. The half width of the emission spectrum of the fluorescent material is preferably 20 nm or more and 50 nm or less.

As a fluorescent substance whose peak wavelength of the emission spectrum in a toluene solution is 440 nm - 460 nm, it is preferable to use the substance which has an aromatic diamine skeleton, for example. More preferably, a material having a pyrenediamine skeleton is used. As a material having a pyrene diamine skeleton, more specifically, an organic compound in which two benzo[ b ]naphtho[1,2- d ]furanylamine skeletons are bonded to a pyrene skeleton, represented by the following general formula (G1) It is preferable to use In addition, the fluorescent substance which can be used in this embodiment is not limited to the following example.

As an organic compound in which two benzo[ b ]naphtho[1,2- d ]furanylamine skeletons are bonded to a pyrene skeleton, an organic compound represented by the following general formula (G1) can be used. In addition, the organic compound represented by the following general formula (G1) exhibits blue fluorescence.

In the general formula (G1), Ar ¹ and Ar ² each independently represent a substituted or unsubstituted aryl group having 6 to 13 carbon atoms to form a ring; R ¹ to R ⁸ , R ¹⁰ to R ¹⁸ , and R ²⁰ to R ²⁸ are each independently hydrogen, a substituted or unsubstituted C 1 to C 6 alkyl group, a substituted or unsubstituted C 1 to C 6 alkoxy group, a cyano group, halogen, a substituted or unsubstituted haloalkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 10 carbon atoms.

Embodiment 2 can be referred to for specific examples of the organic compound represented by general formula (G1).

There is no particular limitation on the material that can be used as the light emitting material of the other of the light emitting layers 106a and 106b, and a light emitting material that converts singlet excitation energy into light emission in the visible light region, or converts triplet excitation energy into light emission in the visible light region. A luminescent material that converts can be used.

As an example of a light-emitting material that converts singlet excitation energy into light emission in the visible region, a material that emits fluorescence is exemplified. Examples of substances emitting fluorescence include pyrene derivatives, anthracene derivatives, triphenylene derivatives, fluorene derivatives, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, dibenzoquinoxaline derivatives, quinoxaline derivatives, pyridine derivatives, pyrimidine derivatives, phenanthrene derivatives, and naphthalene derivatives. A pyrene derivative is particularly preferable because of its high emission quantum yield. Specific examples of the pyrene derivative include N , N' -bis(3-methylphenyl) -N , N' -bis[3-(9-phenyl- 9H -fluoren-9-yl)phenyl]pyrene-1,6 -Diamine ( 1,6mMemFLPAPrn ), N , N' -bis[4-(9-phenyl-9H-fluoren-9-yl)phenyl] -N , N' -diphenylpyrene-1,6-dia Min(1,6FLPAPrn), N , N' -bis(dibenzofuran-2-yl) -N , N' -diphenylpyrene-1,6-diamine (1,6FrAPrn), and N , N'- bis(dibenzothiophen-2-yl) -N , N' -diphenylpyrene-1,6-diamine (1,6ThAPrn).

Examples of luminescent materials that convert triplet excitation energy into luminescence in the visible region include materials that emit phosphorescence and thermally activated delayed fluorescence (TADF) materials. In addition, TADF materials can up-convert triplet excited states to singlet excited states using little thermal energy (i.e., inverse-to-inverse crossover is possible) and efficiently emit light from singlet excited states. (fluorescence) is shown. TADF is efficiently obtained under the condition that the energy difference between the triplet excitation level and the singlet excitation level is 0 eV or more and 0.2 eV or less, preferably 0 eV or more and 0.1 eV or less. In addition, "delayed fluorescence" represented by TADF refers to light emission having the same spectrum as normal fluorescence and having a very long lifetime. Its lifetime is at least 10 ^-6 seconds, preferably at least 10 ^-3 seconds.

As the phosphorescence-emitting substance, an iridium-based, rhodium-based, or platinum-based organometallic complex or metal complex can be used, and an organic iridium complex such as an iridium-based orthometal complex is particularly preferable. Examples of the orthometalated ligand include 4H-triazole ligand, 1H - triazole ligand, imidazole ligand, pyridine ligand, pyrimidine ligand, pyrazine ligand, and isoquinoline ligand. As a metal complex, the platinum complex etc. which have a porphyrin ligand are mentioned. Examples of phosphorescent-emitting materials include bis[2-(3',5'-bistrifluoromethylphenyl)pyridinato- N , C2 ^' ]iridium(III)picolinate (abbreviated as Ir(CF) ₃ ppy) ₂ (pic)), bis[2-(4',6'-difluorophenyl)pyridinato ^- N , C2 ^' ]iridium(III)acetylacetonate (abbreviation: FIracac), tris (2-phenylpyridinato)iridium(III) (abbreviation: Ir(ppy) ₃ ), bis(2-phenylpyridinato)iridium(III)acetylacetonate (abbreviation: Ir(ppy) ₂ (acac) )), tris (acetylacetonato) (monophenanthroline) terbium (III) (abbreviation: Tb (acac) ₃ (Phen)), bis (benzo [ h ] quinolinato) iridium (III) acetyl aceto nate (abbreviated: Ir(bzq) ₂ (acac)), bis(2,4-diphenyl-1,3-oxazolato- N , C ^{2 '} )iridium(III)acetylacetonate (abbreviated: Ir(dpo) ) ₂ (acac)), bis{2-[4′-(perfluorophenyl)phenyl]pyridinato ^- N , C2 ^′ }iridium(III)acetylacetonate (abbreviation: Ir(p-PF-) ph) ₂ (acac)), bis(2-phenylbenzothiazolato- N , C ^{2 '} )iridium(III)acetylacetonate (abbreviated: Ir(bt) ₂ (acac)), bis[2-(2) '-benzo [4,5- α ] thienyl) pyridinato- N , C ^{3 '} ] iridium (III) acetylacetonate (abbreviation: Ir (btp) ₂ (acac)), bis (1-phenyl Isoquinolinato- N , C2 ^' )iridium(III)acetylacetonate (abbreviated: Ir(piq) ₂ (acac)), (acetylacetonato)bis[2,3-bis(4-fluoro Phenyl) quinoxalinato] iridium (III) (abbreviation: Ir (Fdpq) ₂ (acac)), (acetylacetonato) bis (3,5-dimethyl-2-phenylpyrazinato) iridium (III) (abbreviation: [Ir(mppr-Me) ₂ (acac)]), (acetylacetonato)bis(5-isopropyl-3-methyl-2-phenylpyrazinato)iridium(III) (abbreviation: [Ir (mppr-iPr) ₂ (acac)]), (acetylacetonato) Bis(2,3,5-triphenylpyrazinato)iridium(III) (abbreviation: Ir(tppr) ₂ (acac)), bis(2,3,5-triphenylpyrazinato) (dipivaloyl Metanato) iridium (III) (abbreviation: [Ir(tppr) ₂ (dpm)]), (acetylacetonato)bis(6- tert -butyl-4-phenylpyrimidinato)iridium (III) ( Abbreviation: [Ir(tBuppm) ₂ (acac)]), (acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(III) (abbreviation: [Ir(dppm) ₂ (acac)] ), 2,3,7,8,12,13,17,18- octaethyl -21H, 23H -porphyrin platinum(II) (abbreviation: PtOEP), tris(1,3-diphenyl-1,3 -propanedioneto) (monophenanthroline) europium (III) (abbreviated: Eu(DBM) ₃ (Phen)), and tris[1-(2-thenoyl)-3,3,3-trifluoro roacetonato] (monophenanthroline) europium (III) (abbreviation: Eu(TTA) ₃ (Phen)).

Specific examples of the TADF material include fullerene, its derivatives, acridine derivatives such as proplavin, and eosin. Other examples include metal-containing porphyrins, such as porphyrins containing magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), or palladium (Pd). do. Examples of metal-containing porphyrins include protoporphyrin-tin fluoride complex (SnF ₂ (Proto IX)), mesoporphyrin-tin fluoride complex (SnF ₂ (Meso IX)), hematoporphyrin-tin fluoride complex (SnF ₂ ) (Hemato IX)), coproporphyrin tetramethyl ester-fluorinated tin complex (SnF ₂ (Copro III-4Me)), octaethylporphyrin-tin fluorinated complex (SnF ₂ (OEP)), ethioporphyrin-fluorinated tin complex (SnF ₂ (Etio I)), and octaethylporphyrin-platinum chloride complex (PtCl ₂ OEP). or 2-(biphenyl-4-yl)-4,6-bis(12-phenylindolo[2,3-a]carbazol-11-yl)-1,3,5-triazine (PIC- TRZ) and the like can be used a heterocyclic compound including a π-electron-rich heteroaromatic ring and a π-electron-deficient heteroaromatic ring. In addition, the material in which the π-electron-rich heteroaromatic ring is directly bonded to the π-electron-deficient heteroaromatic ring increases both the donor property of the π-electron-rich heteroaromatic ring and the acceptor property of the π-electron-sufficient heteroaromatic ring, and the S ₁ level and T Since the energy difference of ₁ level becomes small, it is especially preferable.

As a material usable as the light emitting material of the other of the light emitting layers 106a and 106b, it is preferable to use a light emitting material that converts triplet excitation energy into light emission in the visible region. More preferably, a phosphorescent material exhibiting yellow phosphorescence is used. With this structure, a light emitting device with low power consumption can be obtained. By using such a light emitting element as a display element of a light emitting device, the power consumption at the time of obtaining white light emission can be reduced effectively.

When an electron transporting material is used as the organic compound of the light emitting layers 106a and 106b, a π-electron deficient heteroaromatic compound such as a nitrogen-containing heteroaromatic compound is preferable, and examples thereof include 2-[3-(dibenzothiophene- 4-yl)phenyl]dibenzo[ f , h ]quinoxaline (abbreviation: 2mDBTPDBq-II), 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[ f , h ]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[4-(3,6-diphenyl-9H-carbazol-9-yl)phenyl]dibenzo[ f , h ]quinoxaline ( abbreviation: 2CzPDBq-III), 7-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[ f , h ]quinoxaline (abbreviation: 7mDBTPDBq-II), and 6-[3-(dibenzothiophene) quinoxaline derivatives and dibenzoquinoxaline derivatives such as -4-yl)phenyl]dibenzo[ f , h ]quinoxaline (abbreviation: 6mDBTPDBq-II).

When a hole transporting material is used as the organic compound of the light emitting layers 106a and 106b, a π-electron excess heteroaromatic compound (eg, a carbazole derivative or an indole derivative) or an aromatic amine compound is preferable, for example, 4- Phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP ), 4,4'-di(1-naphthyl)-4''-(9-phenyl -9H-carbazol-3-yl)triphenylamine (abbreviation: PCBNBB ), 3-[ N- (1-naphthyl ) -N-(9-phenylcarbazol-3-yl)amino]-9- Phenylcarbazole (abbreviation: PCzPCN1), 4,4',4''-tris[ N- (1-naphthyl) -N -phenylamino]triphenylamine (abbreviation: 1'-TNATA), 2,7- Bis[ N- (4-diphenylaminophenyl) -N -phenylamino]-spiro-9,9'-bifluorene (abbreviation: DPA2SF), N , N' -bis(9-phenylcarbazole-3 -yl) -N , N' -diphenylbenzene-1,3-diamine (abbreviation: PCA2B ), N- (9,9-dimethyl-2-diphenylamino-9H-fluoren-7-yl ) diphenylamine (abbreviation: DPNF), N , N ', N ''-triphenyl- N , N ', N ''-tris(9-phenylcarbazol-3-yl)benzene-1,3,5 -Triamine (abbreviation: PCA3B), 2-[ N- (9-phenylcarbazol-3-yl) -N -phenylamino]spiro-9,9'-bifluorene (abbreviation: PCASF), 2- [ N- (4-diphenylaminophenyl) -N -phenylamino]spiro-9,9'-bifluorene (abbreviation: DPASF), N , N' -bis[4-(carbazol-9-yl) )phenyl] -N , N' -diphenyl-9,9-dimethylfluorene-2,7-diamine (abbreviation: YGA2F ), 4,4'-bis[ N- (3-methylphenyl)-N- Phenylamino]biphenyl (abbreviation: TPD), 4,4'-bis[ N- (4-diphenylaminophenyl) -N -phenylamino]biphenyl (abbreviation: DPAB), N- (9,9-di Methyl -9H-fluoren-2-yl)-N- { 9,9-dimethyl-2-[ N' -phenyl- N '-(9,9- dimethyl -9H-fluorene-2- yl)amino] -9H -fluoren-7-yl}phenyl Amine (abbreviation: DFLADFL), 3-[ N- (9-phenylcarbazol-3-yl) -N -phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3-[ N- (4-di Phenylaminophenyl) -N -phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA1), 3,6-bis[ N- (4-diphenylaminophenyl) -N -phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA2), 4,4'-bis( N- {4-[ N '-(3-methylphenyl)-N'-phenylamino]phenyl} -N -phenylamino ) biphenyl (abbreviation: DNTPD), 3,6-bis[ N- (4-diphenylaminophenyl)-N-(1-naphthyl)amino]-9-phenylcarbazole (abbreviation: PCzTPN2), and 3,6-bis[ N- (9 ) -phenylcarbazol-3-yl) -N -phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2).

When the light emitting material used for the light emitting layer is a material that emits phosphorescence, examples of the organic compound used for the light emitting layer include zinc-based or aluminum-based metal complexes, oxadiazole derivatives, triazole derivatives, benzimidazole derivatives, quinoxaline derivatives, In addition to dibenzoquinoxaline derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, pyrimidine derivatives, triazine derivatives, pyridine derivatives, bipyridine derivatives, and phenanthroline derivatives, aromatic amine and carbazole derivatives are included.

When the light emitting material used for the light emitting layer is a material emitting fluorescence, it is preferable to use an anthracene derivative or a tetracene derivative having a high S ₁ level and a low T ₁ level. Specific examples include 9-phenyl-3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole ( PCzPA ), 9-[4-(10-phenyl-9-anthracenyl) Phenyl]-9H-carbazole ( CzPA ), 7-[4-(10-phenyl-9-anthryl)phenyl]-7H-dibenzo[ c , g ]carbazole ( cgDBCzPA ), 6-[3 -(9,10-diphenyl-2-anthryl)phenyl]-benzo[ b ]naphtho[1,2- d ]furan (2mBnfPPA), 9-phenyl-10-{4-(9-phenyl-9) H -fluoren-9-yl)biphenyl-4'-yl}anthracene (FLPPA), 5,12-diphenyltetracene, and 5,12-bis(biphenyl-2-yl)tetracene .

The electron transporting layers 107a and 107b are layers containing a material having high electron transporting properties. The electron transport layers 107a and 107b include Alq ₃ , tris(4-methyl-8-quinolinolato)aluminum (abbreviation: Almq ₃ ), and bis(10-hydroxybenzo[ h ]quinolinolato)beryllium (II). ) (abbreviation: BeBq ₂ ), BAlq, Zn(BOX) ₂ , or metal complexes such as bis[2-(2-hydroxyphenyl)benzothiazolato]zinc(II) (abbreviation: Zn(BTZ) ₂ ) can be used In addition, 2-(4-biphenylyl)-5-(4- tert -butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis[5-( p - tert ) -Butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (abbreviation: OXD-7), 3-(4- tert -biphenylyl)-4-phenyl-5-(4-butyl Phenyl)-1,2,4-triazole (abbreviation: TAZ), 3-(4- tert -butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenylyl)-1,2 ,4-triazole (abbreviation: p-EtTAZ), vasophenanthroline (abbreviation: BPhen), vasocuproin (abbreviation: BCP), or 4,4'-bis(5-methylbenzoxazole-2- A heteroaromatic compound such as yl) stilbene (abbreviation: BzOs) may also be used. Alternatively, poly(2,5-pyridinediyl) (abbreviation: PPy), poly[(9,9-dihexylfluorene-2,7-diyl) -co- (pyridine-3,5-diyl) ] (abbreviation: PF-Py), or poly[(9,9-dioctylfluorene-2,7-diyl) -co- (2,2'-bipyridine-6,6'-diyl)] (abbreviation: PF-BPy) can be used. The materials mentioned here are mainly materials with an electron mobility of 1×10 ^-6 cm ² /Vs or more. However, any material other than the above-mentioned materials may be used for the electron transporting layers 107a and 107b as long as the electron transporting property is higher than the hole transporting property.

Each of the electron transporting layers 107a and 107b is not limited to a single layer, but may be a laminate including two or more layers containing any of the above-mentioned materials.

The electron injection layers 108a and 108b are layers containing a material having high electron injection property. In the electron injection layers 108a and 108b, an alkali metal such as lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF ₂ ), or lithium oxide (LiO _x ), alkaline earth metal, or these compounds may be used. It is also possible to use rare earth metal compounds such as erbium fluoride (ErF ₃ ). An electride may be used for the electron injection layers 108a and 108b. Examples of the electron oxide include a material in which electrons are added in a high concentration to calcium oxide-aluminum oxide. Any of the materials for forming the above-described electron transport layers 107a and 107b may be used.

Each of the electron injection layers 108a and 108b may be formed using a composite material in which an organic compound and an electron donor are mixed. Since electrons are generated in the organic compound by the electron donor, the composite material has excellent electron injection properties and electron transport properties. In this case, the organic compound is preferably a material excellent in transport of the generated electrons. Specifically, for example, a material (eg, a metal complex or a heteroaromatic compound) for forming the above-described electron transport layers 107a and 107b may be used. As the electron donor, a substance exhibiting electron donor property to an organic compound may be used. Specifically, alkali metals, alkaline earth metals, and rare earth metals are preferable, and lithium, cesium, magnesium, calcium, erbium, and ytterbium are exemplified. Moreover, alkali metal oxides or alkaline earth metal oxides are preferable, and lithium oxide, calcium oxide, and barium oxide are mentioned. Lewis bases, such as magnesium oxide, can also be used. An organic compound such as tetrathiofulvalene (abbreviation: TTF) can also be used.

In the light emitting element described in this embodiment, the optical path length between the second electrode 102 and the light emitting region of the EL layer 103b closest to the second electrode 102 is preferably smaller than λ/4, where λ is the wavelength of light emitted from the light emitting region. For this reason, by appropriately adjusting the total thickness of the electron transport layer 107b and the electron injection layer 108b, the gap between the second electrode 102 and the light emitting region of the EL layer 103b closest to the second electrode 102 is adjusted. It is preferable to make the optical path length smaller than ?/4.

The charge generating layer 109 may have either a structure in which an electron acceptor (acceptor) is added to a hole transport material and a structure in which an electron donor (donor) is added to an electron transport material. Alternatively, both of these structures may be laminated.

In the case of a structure in which an electron acceptor is added to a hole transport material, as a hole transport material, for example, NPB, TPD, TDATA, MTDATA, or 4,4'-bis[ N- (spiro-9,9'-bi) An aromatic amine compound such as fluoren-2-yl) -N -phenylamino]biphenyl (abbreviation: BSPB) can be used. The materials listed here are mainly materials with hole mobility of 10 ^-6 cm ² /Vs or more. In addition, any substance other than the above-mentioned substances may be used as long as the hole transporting property is higher than the electron transporting property.

Examples of electron acceptors include 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviated as F ₄ -TCNQ), chloranyl, and HAT-CN. do. Oxides of metals belonging to groups 4 to 8 of the periodic table may be used. Specifically, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, and rhenium oxide are preferable because of their high electron-accepting properties. Of these, molybdenum oxide is particularly preferable because it is stable in the atmosphere, has low hygroscopicity, and is easy to handle.

On the other hand, in the case of a structure in which an electron donor is added to an electron transport material, as the electron transport material, for example, a metal complex having a quinoline skeleton or a benzoquinoline skeleton, such as Alq, Almq ₃ , BeBq ₂ , or BAlq can be used. . Alternatively, a metal complex having an oxazole-based ligand or a thiazole-based ligand, such as Zn(BOX) ₂ or Zn(BTZ) ₂ , may be used. Alternatively, in addition to these metal complexes, PBD, OXD-7, TAZ, BPhen, or BCP may be used. The materials listed here are mainly materials with an electron mobility of 10 ^-6 cm ² /Vs or more. In addition, any substance other than the substances enumerated herein may be used as long as the electron transporting property is higher than the hole transporting property.

As the electron donor, alkali metals, alkaline earth metals, rare earth metals, metals belonging to Group 2 or 13 of the periodic table, or oxides or carbonates thereof can be used. Specifically, lithium (Li), cesium (Cs), magnesium (Mg), calcium (Ca), ytterbium (Yb), indium (In), lithium oxide, or cesium carbonate is preferably used. Alternatively, an organic compound such as tetrathianaphthacene may be used as the electron donor.

In addition, by forming the charge generating layer 109 using any of the above materials, it is possible to suppress the increase in the driving voltage caused by laminating the EL layers.

In addition, the hole injection layers 104a and 104b, the hole transport layers 105a and 105b, the light emitting layers 106a and 106b, the electron transport layers 107a and 107b, the electron injection layers 108a and 108b, and the charge generation layer 109. Each may be formed by a deposition method (eg, a vacuum deposition method), an inkjet method, or a coating method.

Although this embodiment describes a light emitting element having two EL layers, a light emitting element in which three or more EL layers are laminated may be used.

Further, the light emitting element of the present invention may have a single structure of one EL layer as shown in Fig. 1B. In this case, the light emitting layer 106 includes a first light emitting layer 106a and a second light emitting layer 106b. For the structure of other components, reference may be made to the description of the layers indicated by the same reference numerals described above.

In the case of the single structure, the luminous efficiency may be improved by the divided coloring structure shown in FIG. 27 . Even when coloring is performed only once, the luminous efficiency of the light emitting device of the structure shown in FIG. 27 can be made equal to that of a light emitting device in which the light emitting layers are separated and colored (in the case of blue and yellow, coloring is performed twice).

In the separate colored structure, the substrate 1100, the first electrodes 1102B, 1102G, 1102R, and 1102Y provided on the substrate 1100, the second electrode 1104, the black matrix 1105, the color filters 1106B, 1106G, 1106R, and 1106Y), and the sealing substrate 1101 are similar to the components of FIGS. 1A and 1B. As for the EL layer, the hole injection layer and the hole transport layer 1103e, the yellow light emitting layer 1103f, and the electron transport layer and the electron injection layer 1103h can be used for all the light emitting devices, and only the blue light emitting layer 1103d is colored separately. It is provided on a portion where a blue light emitting device is formed.

Here, in the yellow light emitting layer 1103f and the blue light emitting layer 1103d, the carrier balance is adjusted so that a recombination region can be formed on the electrode side closer to the separately colored light emitting layer (in this case, the blue light emitting layer). In Fig. 27, since the blue light emitting layer 1103d is separately colored and is closer to the first electrode (here, the anode) than the yellow light emitting layer, the host material and the light emitting material of the blue light emitting layer and the yellow light emitting layer are selected from the electrons of each of the blue light emitting layer and the yellow light emitting layer. It is selected so that transportability is higher than hole transportability. With this structure, only blue light emission can be obtained from the light emitting device including the blue light emitting layer 1103d, and only yellow light can be obtained from other devices, and the luminous efficiency is equal to that of a device colored by dividing the blue light emitting layer and the yellow light emitting layer. can be

The light emitting mechanism of the above-described light emitting device depends on the structure of the light emitting layer, which will be described below with reference to FIGS. 2, 3, and 4 .

(1) First, the light emitting layer 106a or 106b contains a light emitting material (guest material 121) and a first organic compound (host material 122), and the light emitting material (guest material 121) emits fluorescence. Two types of light emitting mechanisms in the case of a material that does

In addition, in the light emitting layer 106a or 106b, an excited state is formed by recombination of carriers, and since the host material 122 is present in a larger amount than the guest material 121 , the excited state is mainly caused by the excitation of the host material 122 . formed as a state. Here, the ratio of the singlet excited state to the triplet excited state formed by recombination of carriers (hereinafter, exciton generation probability) is about 1:3.

(i) when the T _{1 level of the host material 122 is higher than the T 1 level} of the guest material 121

Energy transfers (triplet energy transfer) from the host material 122 to the guest material 121 in the triplet excited state, but since the guest molecule is a fluorescent material, that triplet excited state does not provide luminescence. In addition, since a small amount of the guest molecule is present in the light emitting layer, triplet-triplet annihilation (TTA) is difficult to occur, so that the triplet excited state of the guest molecule is thermally inactivated. Therefore, triplet excitons cannot be used for light emission, and at most about 25% of the injected carriers can be used for light emission.

(ii) when the T _{1 level of the host material 122 is lower than the T 1 level} of the guest material 121

The correlation between the energy levels of the host material 122 and the guest material 121 is shown in FIG. 2 . What the terms and symbols in Figure 2 indicate are as follows:

Guest: guest material 121 (fluorescent material);

Host: host material 122;

S _FH : the level of the lowest singlet excited state of the host material 122;

T _FH : the level of the lowest triplet excited state of the host material 122;

S _FG : the level of the lowest singlet excited state of the guest material 121 (fluorescent material); and

T _FG : The level of the lowest triplet excited state of the guest material 121 (fluorescent material).

In this case, since the host molecule is present in a large amount in the light emitting layer, triplet-triplet annihilation (TTA) is likely to occur, so that some of the triplet excitons of the host material 122 are the lowest singlet of the host material 122 . It is converted to the level of the excited state (S _FH ). Then, energy moves from the lowest singlet excited state level (S _FH ) of the host material 122 to the lowest singlet excited state level (S _FG ) of the guest material 121 (path A). As a result, the guest material 121 emits light.

Since the T ₁ level (T _FH ) of the host material 122 is lower than the T ₁ level (T _FG ) of the guest material 121 , even when the carriers recombine directly in the guest material 121 to generate triplet excitons. , energy travels (path B) from the T ₁ level (T _FG ) to the T ₁ level (T _FH ) of the host material 122 and is available for TTA. As a result, the luminous efficiency may be improved compared to the case (i) described above.

(2) Next, the light emitting layer 106a or 106b contains a light emitting material (guest material 131), a first organic compound 132, and a second organic compound 133, and a light emitting material (guest material 131) )) is a material that emits phosphorescence, and the luminescence mechanism will be described. In addition, the first organic compound 132 acts as a host material, and the weight ratio of the first organic compound 132 in the emission layer is greater than the weight ratio of the second organic compound 133 in the emission layer.

In the light emitting layer 106a or 106b, there is no particular limitation on the combination as long as the first organic compound 132 and the second organic compound 133 can form an exciplex (exciplex) 134, but one of these is a material having hole transport properties and the other is preferably a material having electron transport properties. In that case, a donor-acceptor excited state is easily formed, whereby the exciplex 134 can be efficiently formed. When the combination of the first organic compound 132 and the second organic compound 133 is a combination of a material having a hole transport property and a material having an electron transport property, the carrier balance can be easily controlled by adjusting the mixing ratio. Specifically, the ratio of the material having the hole transport property to the material having the electron transport property is preferably 1:9 to 9:1 (weight ratio). Since the carrier balance can be easily controlled by the above structure, the recombination region can also be easily controlled.

The correlation between the energy levels of the light emitting material (guest material) 131 , the first organic compound 132 , and the second organic compound 133 is shown in FIG. 3 . What the terms and symbols in Figure 3 indicate are as follows:

Guest: guest material (phosphorescent material) 131;

a first organic compound: a first organic compound (132);

a second organic compound: a second organic compound (133);

exciplex: exciplex (exciplex) (134);

S _PH : the level of the lowest singlet excited state of the first organic compound 132;

T _PH : the level of the lowest triplet excited state of the first organic compound 132;

T _PG : the level of the lowest triplet excited state of the guest material (phosphor material) 131;

S _E : the level of the lowest singlet excited state of the exciplex 134; and

T _E : the level of the lowest triplet excited state of the exciplex (134).

In this case, the first organic compound 132 and the second organic compound 133 form the exciplex 134 . The level of the lowest singlet excited state of the exciplex 134 (S _E ) and the level of the lowest triplet excited state of the exciplex 134 (TE _E ) are close to each other (path C).

In addition, the exciplex 134 is in an excited state formed by two types of materials, and is formed by either optical excitation or electrical excitation. For photoexcitation, exciplex 134 is formed such that one molecule in the excited state of one material pairs with one molecule in the ground state of another. In the case of electrical excitation, there are two patterns in the subprocess in which exciplexes are formed. One of them is the same as in the case of photoexcitation. The other is as follows: the cation molecules (holes) of one material become close to the anion molecules (electrons) of the other material, so that the exciplex 134 is formed. Since the latter sub-process is dominant at the initiation of light emission, the exciplex 134 can be formed without the two types of materials being in an excited state. Therefore, in addition to being able to lower the light emission starting voltage, it is possible to reduce the driving voltage.

When the exciplex 134 is formed, the energy is at the level of the lowest singlet excited state of the exciplex 134 (S _E ) and the level of the lowest triplet excited state of the exciplex 134 (T _E ). It moves (path D) to the lowest triplet excited state level (T _PG ) of the material (phosphor material) 131 , whereby the guest material 131 emits light. In addition, exciplex-triplet energy transfer (ExTET: It is called exciplex-triplet energy transfer).

When the exciplex 134 loses energy and returns to its ground state, the two kinds of materials that formed the exciplex 134 act as the original different materials.

Depending on the combination of the first organic compound and the second organic compound forming the exciplex, the guest material (fluorescent material) is converted by energy transfer from the exciplex to the guest material (fluorescent material) by using a fluorescent material as the guest material. can emit light. Fluorescent materials include heat activated delayed fluorescent materials in their category.

(3) Then, one of the light emitting layers 106a and 106b is formed by the first light emitting layer of the light emitting mechanism (TTA) described in (ii) of (1) above, and the light emitting mechanism (ExTET) described in (2) above. The light emitting mechanism in the case where the second light emitting layer of has a stacked structure in contact with each other will be described. The correlation between the energy levels in this case is shown in FIG. 4 . What the terms and symbols in Figure 4 indicate are as follows:

a first light emitting layer (fluorescence) 113: a first light emitting layer 113;

a second light-emitting layer (phosphorescence) 114: a second light-emitting layer 114;

S _FH : the level of the lowest singlet excited state of the host material 122;

T _FH : the level of the lowest triplet excited state of the host material 122;

S _FG : the level of the lowest singlet excited state of the guest material (fluorescent material) 121;

T _FG : the lowest triplet excited state level of the guest material (fluorescent material) 121;

S _PH : the level of the lowest singlet excited state of the first organic compound 132;

T _PH : the level of the lowest triplet excited state of the first organic compound 132;

T _PG : the level of the lowest triplet excited state of the guest material (phosphor material) 131;

S _E : the level of the lowest singlet excited state of the exciplex 134; and

T _E : the level of the lowest triplet excited state of the exciplex (134).

Since the exciplex 134 formed in the second light emitting layer 114 exists only in an excited state, diffusion of excitons between the exciplexes 134 is difficult to occur. In addition, the excitation level (S _E ) of the exciplex 134 is the singlet excitation level (S _PH ) of the first organic compound 132 in the second light emitting layer 114 and the singlet excitation level of the second organic compound Since it is lower than all, the singlet excitation energy does not diffuse from the exciplex 134 to the first organic compound 132 and the second organic compound. At the interface between the first light emitting layer 113 and the second light emitting layer 114 , energy (especially triplet energy) is formed in the second light emitting layer 114 in the exciplex 134 (the level of the lowest singlet excited state of the exciplex). (S _E ) or the level of the lowest triplet excited state (T _E ) of the exciplex when moving to the excited level (S _FH , T _FH ) of the host material 122 in the first light emitting layer 113 , In the first light emitting layer 113 , singlet excitation energy is converted into light emission through a normal path, and a portion of triplet excitation energy is converted into light emission by TTA. As a result, energy loss can be reduced. In addition, since the diffusion of excitons between exciplexes does not occur, energy transfer from the exciplex to the first light emitting layer 113 occurs only at the interface.

The fact that most excitons exist in an exciplex state in the second light emitting layer 114 and that exciton diffusion between the exciplexes 134 in the second light emitting layer 114 is difficult to occur is the host of the first light emitting layer 113, which is a fluorescent layer. Even when the T ₁ level of the material 122 is lower than the T ₁ level of the first organic compound 132 and the second organic compound 133 of the second light emitting layer 114 , the luminous efficiency of the second light emitting layer 114 is means it can be maintained. That is, in this structure, a condensed aromatic compound such as an anthracene derivative, which is electrochemically stable and highly reliable and has a low triplet excitation level, is used as a host material for the first light emitting layer 113 , so that it is adjacent to the first light emitting layer 113 . Light emission can be efficiently obtained from the phosphorescent layer. Therefore, the T 1 level of the host material 122 in the first light emitting layer 113 is lower than the T ₁ level of the _first organic compound 132 and the second organic compound 133 in the second light emitting layer 114 . It is one of the characteristics of this structure.

In the first light emitting layer 113 , the S ₁ level (not shown) of the host material 122 is preferably higher than the S ₁ level of the guest material 121 , and the T ₁ level (T _FH ) of the host material 122 . is preferably lower than the T ₁ level (T _FG ) of the guest material 121 . With this structure, at the interface between the first light emitting layer 113 and the second light emitting layer 114 , the level of the lowest triplet excited state of the exciplex 134 formed in the second light emitting layer 114 (T _E ) Even if energy transfer to the lowest triplet excited state level (T _FH ) of the host material 122 in the first light emitting layer 113 occurs, the energy in the first light emitting layer 113 is partially converted into light emission by TTA. can As a result, energy loss can be reduced.

When the above-described stacked structure of the light emitting layer is used, it is preferable that the light emitted from the first light emitting layer 113 has a peak on the shorter wavelength side than that of the light emitted from the second light emitting layer 114 . The reason for this is as follows. Since the luminance of a light emitting element using a phosphorescent material that emits light of a short wavelength tends to deteriorate quickly, by using a fluorescent material that emits light of a shorter wavelength than the light emitted from the second light emitting layer 114, the deterioration of the luminance is reduced. Fewer light emitting devices can be provided.

When using the above-described stacked structure of the light emitting layer, a third layer is formed between the first light emitting layer 113 and the second light emitting layer 114 so that the first light emitting layer 113 and the second light emitting layer 114 are not in contact with each other. may be avoided. With this structure, the host material 122 or the guest material in the first light emitting layer 113 in an excited state of the first organic compound 132 or the guest material (phosphorescent material) 131 formed in the second light emitting layer 114 . Energy transfer (especially triplet energy transfer) by the Dexter mechanism to the (fluorescent material) 121 can be prevented. Further, the third layer having such a structure may be formed to a thickness of several nm.

The third layer may be formed using a single material (a hole transport material or an electron transport material), or may be formed using both a hole transport material and an electron transport material. In the case of a single material, a bipolar material may be used. Here, the bipolar material means a material whose ratio of electron mobility to hole mobility is 100 or less. The third layer may be formed using the same material as the first or second light-emitting layer. This structure facilitates fabrication of the light emitting device and reduces the driving voltage.

It is preferable that the light emitting element described in this embodiment has a microcavity structure. Thereby, even when the same EL layer is employed, light (monochromatic light) of different wavelengths can be extracted. Compared with a divisional coloring structure (eg, coloring R, G, and B separately), the above-described structure is advantageous for a full-color display because of the easiness of realization of a display with higher resolution and the like. Combination with a colored layer (color filter) is also possible. The microcavity structure makes it possible to increase the intensity of light having a specific wavelength in the front direction, thereby reducing power consumption. The above-described structure is particularly effective when used as a back light or a front light of a color display (image display device) including pixels of three or more colors, but may be used for a lighting device or the like.

As the light emitting device including the above-described light emitting device, a passive matrix light emitting device and an active matrix light emitting device can be manufactured. Each light emitting device is one embodiment of the present invention.

In the case of manufacturing the active matrix light emitting device, there is no particular limitation on the structure of the transistor (FET). For example, a staggered FET or an inverted staggered FET may be appropriately used. The driving circuit formed on the FET substrate may be formed using both of the n-type FET and the p-type FET, or may be formed using only either one of the n-type FET and the p-type FET. In addition, there is no particular limitation on the crystallinity of the semiconductor film used for the FET. For example, either an amorphous semiconductor film or a crystalline semiconductor film may be used. Examples of semiconductor materials include Group 13 semiconductors (eg, gallium), Group 14 semiconductors (eg, silicon), compound semiconductors (including oxide semiconductors), and organic semiconductors.

In addition, the light emitting element described in this embodiment can be formed on various substrates. There is no particular limitation on the type of the substrate. Examples of the substrate include a semiconductor substrate (eg, a single crystal substrate or a silicon substrate), an SOI substrate, a glass substrate, a quartz substrate, a plastic substrate, a metal substrate, a stainless steel substrate, a substrate comprising a stainless steel foil, a tungsten substrate, tungsten Substrates including foils, flexible substrates, bonding films, papers including fibrous materials, and base material films are included. Examples of the glass substrate include a barium borosilicate glass substrate, an alumino borosilicate glass substrate, and a soda lime glass substrate. Examples of the flexible substrate, bonding film, and base material film include plastics typified by polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polyether sulfone (PES); synthetic resins such as acrylic; polypropylene; polyester; polyvinyl fluoride; polyvinyl chloride; polyamide; polyimide; aramid; epoxy; inorganic vapor deposition film; and paper.

When a transistor is formed on any of these substrates together with a light emitting element, by using a semiconductor substrate, a single crystal substrate, an SOI substrate, etc., a small transistor with small variation in characteristics, size, or shape and high current capability can be obtained. can be produced A circuit using such a transistor realizes low power consumption of the circuit or high integration of the circuit.

When the above-described flexible substrate is used as the substrate for forming the light emitting element or transistor, the light emitting element or transistor may be directly formed on the flexible substrate. Alternatively, part or all of the light emitting element or transistor may be formed on the base substrate through a separation layer, and then the light emitting element or transistor may be separated from the base substrate and transferred to another substrate. As described above, when the light emitting element or transistor is transferred to another substrate using the separation layer, the light emitting element or transistor can be formed on a substrate with low heat resistance or on a flexible substrate on which it is difficult to directly form the light emitting element or transistor. . Examples of the above-described separation layer include a laminate including an inorganic film, for example, a tungsten film and a silicon oxide film, and an organic resin film such as polyimide formed on a substrate. Examples of the substrate for displacing the transistor include, in addition to the above-mentioned substrate on which a transistor can be formed, a paper substrate, a cellophane substrate, an aramid film substrate, a polyimide film substrate, a stone substrate, a wood substrate, a cloth substrate (natural fiber (eg, For example, silk, cotton, or linen), synthetic fibers (such as nylon, polyurethane, or polyester), or regenerated fibers (such as acetate, cupra, rayon) , or recycled polyester), and the like), leather substrates, and rubber substrates. By using any of these board|substrates, durability or heat resistance raise, and weight reduction or thickness reduction can be implement|achieved.

In addition, the structure described in this embodiment can be used in appropriate combination with any structure described in other embodiments.

(Embodiment 2)

In this embodiment, the organic compound represented by general formula (G1) is demonstrated in detail.

In the general formula (G1), Ar ¹ and Ar ² each independently represent a substituted or unsubstituted aryl group having 6 to 13 carbon atoms to form a ring; R ¹ to R ⁸ , R ¹⁰ to R ¹⁸ , and R ²⁰ to R ²⁸ are each independently hydrogen, a substituted or unsubstituted C 1 to C 6 alkyl group, a substituted or unsubstituted C 1 to C 6 alkoxy group, a cyano group, halogen, a substituted or unsubstituted haloalkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 10 carbon atoms. In the material represented by the general formula (G1), when R ¹⁸ and R ²⁸ are each a substituted or unsubstituted phenyl group, it is preferable because the emission wavelength of the material can be shortened. The use of a material in which R ¹⁸ and R ²⁸ is a substituted or unsubstituted phenyl group is preferably used in the light emitting device because the half width of the emission spectrum of the light emitting device is narrowed, the luminous efficiency is increased, and the reliability is increased. In order to prevent the transformation of the three-dimensional structure, it is more preferable that R ¹⁸ and R ²⁸ are an unsubstituted phenyl group. When R ¹⁸ and R ²⁸ are each a phenyl group having a substituent, the substituent is preferably an alkyl group having 1 to 6 carbon atoms or a phenyl group.

As the organic compound represented by the general formula (G1), the use of the organic compound represented by the general formula (G2) is preferable because the emission wavelength can be further shortened.

In the general formula (G2), R ¹ to R ⁸ and R ²⁹ to R ³⁸ are each independently hydrogen, a substituted or unsubstituted C 1 to C 6 alkyl group, or a substituted or unsubstituted C 1 to C 6 alkoxy group , a cyano group, halogen, a substituted or unsubstituted haloalkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 10 carbon atoms.

Specific examples of a substituted or unsubstituted aryl group having 6 to 13 carbon atoms and a substituted or unsubstituted aryl group having 6 to 10 carbon atoms to form a ring in formula (G1) include a phenyl group, 1-naph Tyl group, 2-naphthyl group, ortho -tolyl group, meta -tolyl group, para -tolyl group, ortho -biphenyl group, meta -biphenyl group, para -biphenyl group, 9,9-dimethyl- 9H -fluorene- 2-yl group, 9,9-diphenyl-9H- fluoren -2-yl group, 9H -fluoren-2-yl group, para - tert -butylphenyl group, and mesityl group are included.

Specific examples of the substituted or unsubstituted C1 to C6 alkyl group in the general formulas (G1) and (G2) include a methyl group, an ethyl group, n -propyl group, isopropyl group, n -butyl group, sec -butyl group, isobutyl group tyl group, tert -butyl group, n -pentyl group, isopentyl group, sec -pentyl group, tert -pentyl group, neopentyl group, n -hexyl group, isohexyl group, sec -hexyl group, tert -hexyl group, neo -hexyl group, cyclohexyl group, 3-methylpentyl group, 2-methylpentyl group, 2-ethylbutyl group, 1,2-dimethylbutyl group, and 2,3-dimethylbutyl group are included.

In the general formulas (G1) and (G2), specific examples of a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, cyano group, halogen, and a substituted or unsubstituted haloalkyl group having 1 to 6 carbon atoms include a methoxy group, ethoxy group, n -propoxy group, isopropoxy group, n -butoxy group, sec -butoxy group, isobutoxy group, tert -butoxy group, n -pentyloxy group, isopentyloxy group, sec -pentyloxy group, tert -pentyloxy group, neo-pentyloxy group, n -hexyloxy group, isohexyloxy group, sec -hexyloxy group, tert -hexyloxy group, neo-hexyloxy group, cyclohexyloxy group, 3-methylphen Tyloxy group, 2-methylpentyloxy group, 2-ethylbutoxy group, 1,2-dimethylbutoxy group, 2,3-dimethylbutoxy group, cyano group, fluorine, chlorine, bromine, iodine, and trifluoromethyl groups are included.

In the organic compound, benzonaphthofuranylamine is bonded to each of the 1st and 6th positions of the pyrene skeleton, and the nitrogen atoms of benzonaphthofuranylamine are each independently benzo[ b ]naphtho[1,2- d ]It is bonded to the 6th or 8th position of the furanyl group. Due to the structure in which benzonaphthofuranylamine is bonded to each of the 1st and 6th positions of the pyrene skeleton, the effective conjugated length from the pyrene skeleton to benzonaphthofuranylamine is extended. As a result, it is possible to shift the emission peak wavelength to the longer wavelength side compared to the case of single ring pyrene. In addition, when this structure is used, since the molecular structure is stabilized by the benzonaphthofuranyl group, reliability is expected to be improved. Since the 6-position or 8-position of the benzo[ b ]naphtho[1,2- d ]furanyl group is bonded to the amine skeleton, the color purity of blue may be higher.

When the 8th position of the benzo[ b ]naphtho[1,2- d ]furanyl group is bonded to the amine skeleton, the 6th position of the benzo[ b ]naphtho[1,2- d ]furanyl group is bonded to the amine skeleton It is possible to obtain light emission with a shorter wavelength than the case where it is used. This is because the effective conjugate length is shorter when the 8-position of the benzo[ b ]naphtho[1,2- d ]furanyl group is bonded to the amine backbone. When the 6th-position of the benzo[ b ]naphtho[1,2- d ]furanyl group has an aryl group and the 8th-position of the benzo[ b ]naphtho[1,2- d ]furanyl group is bonded to the amine skeleton, aryl The color purity of blue may be increased by steric hindrance of the group. In addition, since intermolecular interactions are reduced in this structure, high color purity can be maintained even when the concentration of organic compounds is high.

When the above-described organic compound is used as the light emitting material of the light emitting device according to one embodiment of the present invention, the driving voltage for obtaining a desired luminance can be reduced. Moreover, a light emitting element with high reliability can be obtained.

Specific examples of the above-described organic compounds (general formulas (G1) and (G2)) that can be used in the light emitting device according to one embodiment of the present invention are shown (structural formulas (100) to (133)). In addition, the present invention is not limited thereto.

The above-mentioned organic compound emits blue light with high color purity. Blue light emission having chromaticity coordinates determined by the National Television Standards Committee (NTSC), that is, ( x , y )=(0.14, 0.08) or near or deeper blue light emission can be obtained. Therefore, when such an organic compound is used in the light emitting device, the driving voltage of the light emitting device can be lowered and the reliability thereof can be increased. In addition, when such a light emitting element is used, the power consumption of the light emitting device, electronic device, and lighting device of the embodiment of the present invention can be reduced and the lifespan thereof can be prolonged.

In addition, the structure described in this embodiment can be used in appropriate combination with any structure described in other embodiments.

(Embodiment 3)

In this embodiment, one embodiment of a light emitting device in which the light emitting element described in Embodiment 1 is combined with a colored layer (such as a color filter) will be described. In this embodiment, the structure of the pixel portion of the light emitting device will be described with reference to FIG. 5 .

In FIG. 5 , a plurality of FETs 502 are formed on a substrate 501 . Each FET 502 is electrically connected to a light emitting element 507R, 507G, 507B, or 507W. Specifically, each FET 502 is electrically connected to a first electrode 503 that is a pixel electrode of the light emitting element. A partition 504 is provided to cover the ends of the adjacent first electrodes 503 .

In addition, in this embodiment, the 1st electrode 503 functions as a reflective electrode. An EL layer 505 is formed on the first electrode 503 , and a second electrode 510 is formed on the EL layer 505 . The EL layer 505 includes a plurality of light emitting layers each emitting monochromatic light. The second electrode 510 functions as a semi-transmissive/semi-reflective electrode.

The light emitting elements 507R, 507G, 507B, and 507W emit light of different colors. Specifically, the light emitting element 507R is optically adjusted to emit red light, and in the region indicated by 506R, red light is emitted in the direction indicated by the arrow through the coloring layer 508R. The light emitting element 507G is optically adjusted to emit green light, and in the area indicated by 506G, green light is emitted in the direction indicated by the arrow through the coloring layer 508G. The light emitting element 507B is optically adjusted to emit blue light, and in the region indicated by 506B, blue light is emitted in the direction indicated by the arrow through the coloring layer 508B. The light emitting element 507W is optically adjusted to emit white light, and in the area indicated by 506W, white light is emitted in the direction indicated by the arrow without passing through the colored layer.

As shown in Fig. 5, the coloring layers 508R, 508G, and 508B are provided on a transparent sealing substrate 511 provided over the substrate 501 on which the light emitting elements 507R, 507G, 507B, and 507W are formed. The coloring layers 508R, 508G, and 508B are provided so as to overlap each of the light-emitting elements 507R, 507G, and 507B exhibiting different emission colors.

A black layer (black matrix) 509 is provided to cover the ends of the adjacent colored layers 508R, 508G, and 508B. The colored layers 508R, 508G, and 508B and the black layer 509 may be covered with an overcoat layer formed using a transparent material.

Although the above-described light emitting device has a structure in which light is extracted from the sealing substrate 511 side (top emission structure), it may have a structure in which light is extracted from the substrate 501 side on which the FET is formed (bottom emission structure). . Further, in the light emitting device having the top light emitting structure described in this embodiment, a light blocking substrate or a light transmitting substrate can be used as the substrate 501, but in the light emitting device having a bottom light emitting structure, it is necessary to use a light transmitting substrate as the substrate 501 there is

In addition to the structure described above, the structure shown in FIG. 10 may be employed. In FIG. 10 , the structures of light emitting devices 507R, 507G, 507B, and 507Y electrically connected to the FET 502 on the substrate 501 are partially different from those in FIG. 5 . Blue light emission can be obtained by using the fluorescent substance described in Embodiment 1 for the light emitting layer 106a of the EL layer of Embodiment 1. In addition, yellow light emission can be obtained from the light emitting layer 106b of the EL layer of the first embodiment.

In this case, the light emitting elements 507R, 507G, 507B, and 507Y emit light of different colors. Specifically, the light emitting element 507R is optically adjusted to emit red light, and in the region indicated by 506R, red light is emitted in the direction indicated by the arrow through the coloring layer 508R. The light emitting element 507G is optically adjusted to emit green light, and in the area indicated by 506G, green light is emitted in the direction indicated by the arrow through the coloring layer 508G. The light emitting element 507B is optically adjusted to emit blue light, and in the region indicated by 506B, blue light is emitted in the direction indicated by the arrow through the coloring layer 508B. The light emitting element 507Y is optically adjusted to emit yellow light, and in the region indicated by 506Y, yellow light is emitted through the colored layer 508Y in the direction indicated by the arrow.

As shown in Fig. 10, the coloring layers 508R, 508G, 508B, and 508Y are provided on a transparent sealing substrate 511 provided over the substrate 501 on which the light emitting elements 507R, 507G, 507B, and 507Y are formed. . The coloring layers 508R, 508G, 508B, and 508Y are provided so as to overlap each of the light emitting elements 507R, 507G, 507B, and 507Y exhibiting different emission colors.

In the light emitting device according to one embodiment of the present invention, the blue light emitted from the light emitting element 507B and extracted to the outside of the light emitting device through the colored layer 508B has a chromaticity coordinate of ( x , y ) = (0.13 or more and 0.17 or less, 0.03 or more and 0.08 or less) Since deep blue light emission can be obtained, it is preferable. Preferably, the y -coordinate of the blue light emitted from the light emitting element 507B and extracted to the outside of the light emitting device through the colored layer 508B is 0.03 or more and 0.07 or less.

By using blue light emission of such a chromaticity, the luminance of blue light emission required to obtain white light emission can be reduced. Since the amount of current consumed by the blue light-emitting element to obtain a predetermined white light-emitting element is sufficiently larger than the amount of current consumed by the light-emitting element of another color, the effect of reducing the amount of current by reducing the luminance of the blue light required to obtain white light emission is considerable

The current efficiency is generally lowered due to the chromaticity of the desired blue light emission, but the effect of reducing the luminance of the blue light emission required to obtain the white light emission is significant. As a result, the amount of current flowing through the blue light emitting element for obtaining predetermined white light emission is greatly reduced, and the power consumption of the entire light emitting device is reduced.

When the chromaticity of blue light emission corresponds to deep blue as described above, the light emission color obtained by combining blue light emission and yellow light emission may be different, and the third light emission color necessary to obtain a predetermined white light emission may be different. For example, blue light emission has a chromaticity coordinate determined by NTSC, that is, ( x , y )=(0.14, 0.08) or its vicinity, and yellow light emission has ( x , y )=(0.45, 0.54) or its vicinity. In the case of having chromaticity coordinates, in order to obtain white light emission with a chromaticity of about D65, a red light emission component is further required in addition to light emission obtained by combining blue light emission and yellow light emission. On the other hand, blue light emission has a chromaticity coordinate determined by the NTSC or its vicinity, and yellow light emission has a chromaticity coordinate of ( x , y ) = (0.46, 0.53) or a chromaticity coordinate of red light emission (i.e., x is greater than 0.46 and y is less than 0.53), white light emission having a chromaticity of about D65 can be obtained by adding a green light emission component to light emission obtained by combining blue light emission and yellow light emission. However, when the yellow light emission has the chromaticity coordinates of the red light emission (that is, x is greater than 0.46 and y is less than 0.53), the current efficiency of the yellow pixel is lowered due to a decrease in visibility. That is, the effect of reducing power consumption is reduced accordingly.

In this way, the third light emission color necessary for obtaining white light emission with a chromaticity of about D65 depends on the colors of blue light emission and yellow light emission. Green light emission is advantageous because the current efficiency is generally higher than that of red light emission. However, as described above, when the yellow light emission has the chromaticity coordinates of the red light emission (that is, x is greater than 0.46 and y is less than 0.53), the current efficiency of the yellow pixel is lowered due to a decrease in the visibility of the yellow light emission. Since the effect of the fall of the current efficiency of yellow light emission with high visibility is large, it is preferable that the chromaticity of yellow light emission is not close to the chromaticity of red light emission.

When using deep blue luminescence with chromaticity coordinates ( x , y ) = (0.13 or more and 0.17 or less, 0.03 or more and 0.08 or less), the highly visible chromaticity of yellow is maintained (i.e., chromaticity not too close to that of red emission) ), by using green light emission as the third light emission in addition to blue light emission and yellow light emission, white light emission having a chromaticity of about D65 can be obtained. With this structure, since the visibility of yellow light emission is high, the current efficiency can be maintained high. In addition, the luminance of green light emission required in this structure is lower than that in the case of using red light emission as the third light emission. The visibility of green light emission is higher than that of red light emission, and since the current efficiency of a green light emitting element is generally higher than that of a red light emitting element, the amount of current required to obtain the third light emission is greatly reduced. As a result, the driving voltage may be lowered and power consumption may be reduced. In this case, the chromaticity coordinate of the yellow light emission is preferably ( x , y ) = (0.44 or more and 0.46 or less, 0.53 or more and 0.55 or less).

Although the luminance components of the blue light emitting element for obtaining predetermined white light emission and the light emitting element exhibiting the third light emission decrease, this can be compensated by increasing the luminance of the yellow light emitting element. Since the visibility of yellow light emission is very high, the current efficiency of the yellow light emitting device is very high. The increase in power consumption due to the increase in luminance required to obtain yellow light emission can be supplemented by the reduction in power consumption due to the decrease in luminance required for the blue light emitting device and the light emitting device displaying the third light emission. As a result, reduction in power consumption can be realized.

In the xy chromaticity diagram, in order to obtain deep blue light emission with chromaticity coordinates of ( x , y ) = (0.13 or more and 0.17 or less, 0.03 or more and 0.08 or less), preferably (0.13 or more and 0.17 or less, 0.03 or more and 0.07 or less), The peak wavelength of the emission spectrum of the fluorescent material contained in the first light emitting element in the toluene solution of the fluorescent material is set to 440 nm or more and 460 nm or less, preferably 440 nm or more and 455 nm or less. The chromaticity of the blue light emitting element can be adjusted using a color filter or the like, but since only a small amount of the light of the above-mentioned wavelength is removed by the color filter, light emission from the fluorescent material can be efficiently utilized. Therefore, the half width of the emission spectrum of the fluorescent material in the toluene solution is preferably 20 nm or more and 50 nm or less.

By using blue light emission of such chromaticity, power consumption for obtaining white light emission of about D65 with chromaticity coordinates ( x , y ) = (0.313, 0.329) in the xy chromaticity diagram can be reduced. Specifically, when white light emission with a chromaticity coordinate of ( x , y ) = (0.313, 0.329) in the xy chromaticity diagram is obtained with a luminance of 300 cd/m ² , the power consumption of the light emitting device excluding the power consumption of the driving FET is 1 mW/ cm ² or more and 7 mW/cm ² or less, and the power consumption of the light emitting device including the power consumption of the driving FET (power consumption calculated from the product of the current consumption and the voltage between the anode and the cathode) is 2 mW/cm ² or more and 15 mW /cm ² or less can be made.

With the above-described structure, it is possible to provide light emitting elements emitting a plurality of light emitting colors (red, blue, green, and yellow), and in addition, a light emitting device capable of emitting white light with high efficiency by a combination of these light emitting colors can provide

Various substrates can be used for the light emitting device according to one embodiment of the present invention. There is no particular limitation on the type of the substrate. Examples of the substrate include a semiconductor substrate (eg, a single crystal substrate or a silicon substrate), an SOI substrate, a glass substrate, a quartz substrate, a plastic substrate, a metal substrate, a stainless steel substrate, a substrate including a stainless steel foil, a tungsten substrate, tungsten Substrates including foils, flexible substrates, bonding films, papers including fibrous materials, and base material films are included. Examples of the glass substrate include a barium borosilicate glass substrate, an alumino borosilicate glass substrate, and a soda lime glass substrate. Examples of the flexible substrate, bonding film, and base material film include plastics typified by polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyether sulfone (PES), and polytetrafluoroethylene (PTFE); acryl; polypropylene; polyester; polyvinyl fluoride; polyvinyl chloride; polyamide; polyimide; aramid; epoxy; inorganic vapor deposition film; and paper.

By using a semiconductor substrate, a single crystal substrate, an SOI substrate, or the like for the transistor, it is possible to manufacture a small-sized transistor with small variation in characteristics, size, or shape, and high current capability. A circuit using such a transistor realizes low power consumption of the circuit or high integration of the circuit.

A semiconductor device such as a transistor may be formed after providing a separation layer on the substrate. The separation layer can be used when part or all of a semiconductor device formed on the separation layer is separated from the substrate and transferred to another substrate. In this case, the transistor can also be transferred to a substrate having low heat resistance or a flexible substrate. Examples of the above-described separation layer include a laminate including an inorganic film, for example, a tungsten film and a silicon oxide film, and an organic resin film such as polyimide formed on a substrate.

In other words, after a transistor or light emitting element is formed using one substrate, the transistor or light emitting element may be transferred to another substrate. Examples of the substrate for disposing the transistor or light emitting element include, in addition to the above-described substrate on which a transistor can be formed, a paper substrate, a cellophane substrate, an aramid film substrate, a polyimide film substrate, a stone substrate, a wood substrate, a cloth substrate (natural fiber) (eg, silk, cotton, or hemp), synthetic fibers (eg, nylon, polyurethane, or polyester), or recycled fibers (eg, acetate, cupra, rayon, or recycled polyester) etc.), leather substrates, and rubber substrates. By using such a substrate, a transistor having excellent characteristics or low power consumption can be formed, a device having high resistance and high heat resistance can be provided, or weight reduction or thickness reduction can be realized. Moreover, when manufacturing a flexible light emitting device, you may form a transistor or a light emitting element directly on a flexible substrate.

In addition, the structure described in this embodiment can be used in appropriate combination with any structure described in other embodiments.

(Embodiment 4)

In this embodiment, a light emitting device including a light emitting element according to one embodiment of the present invention will be described.

The light emitting device may be either a passive matrix light emitting device or an active matrix light emitting device. In addition, any light emitting element described in another embodiment can be used for the light emitting device described in this embodiment.

In this embodiment, an active matrix light emitting device will be described with reference to FIGS. 6A and 6B.

6A is a top view of the light emitting device, and FIG. 6B is a cross-sectional view taken along the chain line A-A' of FIG. 6A. In the active matrix light emitting device of this embodiment, the pixel portion 602 , the driver circuit portion (source line driver circuit) 603 , and the driver circuit portions (gate line driver circuit) 604a and 604b are provided over the element substrate 601 . has been The pixel portion 602 , the driver circuit portion 603 , and the driver circuit portions 604a and 604b are sealed with a sealant 605 between the element substrate 601 and the sealing substrate 606 .

Further, a lead wiring 607 for connecting an external input terminal is provided over the element substrate 601 . A signal (eg, a video signal, a clock signal, a start signal, or a reset signal) or a potential is transmitted to the driving circuit section 603 and the driving circuit sections 604a and 604b from the outside via the external input terminal. Here, a flexible printed circuit (FPC) 608 is provided as an example of an external input terminal. Although only the FPC is shown here, the FPC may be provided with a printed wiring board (PWB). In the present specification, the light emitting device includes not only the light emitting device itself, but also a light emitting device provided with an FPC or PWB.

Next, the cross-sectional structure will be described with reference to FIG. 6B. A driver circuit portion and a pixel portion are formed on the element substrate 601, and a driver circuit portion 603 and a pixel portion 602, which are source line driver circuits, are shown here.

As an example of the driving circuit portion 603 , the FET 609 and the FET 610 are combined. Note that the driving circuit section 603 may be formed of a circuit including transistors of the same conductivity type (n-channel transistor or p-channel transistor), or may be formed of a CMOS circuit including n-channel transistors and p-channel transistors. In this embodiment, the driving circuit is integrated with the substrate, but it is not necessary to form the driving circuit on the substrate, and may be formed outside the substrate.

The pixel portion 602 includes a switching FET 611 , a current control FET 612 , and a first electrode (anode) 613 electrically connected to a wiring (source electrode or drain electrode) of the current control FET 612 . It includes a plurality of pixels each including. In this embodiment, the pixel portion 602 includes, but is not limited to, two FETs: a switching FET 611 and a current control FET 612 . The pixel portion 602 may include, for example, three or more FETs and a capacitor in combination.

As the FETs 609, 610, 611, and 612, for example, a staggered transistor or an inverted staggered transistor can be used. Examples of semiconductor materials that can be used for FETs 609, 610, 611, and 612 include group 13 semiconductors (eg, gallium), group 14 semiconductors (eg, silicon), compound semiconductors, oxide semiconductors, and organic semiconductors. In addition, there is no particular limitation on the crystallinity of the semiconductor material, and an amorphous semiconductor or a crystalline semiconductor can be used. In particular, it is preferable to use an oxide semiconductor for the FETs 609, 610, 611, and 612. Examples of the oxide semiconductor include In-Ga oxide and In- M -Zn oxide ( M is Al, Ga, Y, Zr, La, Ce, or Nd). For example, using an oxide semiconductor with an energy gap of at least 2 eV, preferably at least 2.5 eV, and more preferably at least 3 eV in the FETs 609, 610, 611, and 612 can reduce the off-state current of the transistor. .

An insulator 614 is formed to cover the end of the first electrode 613 . In this embodiment, the insulator 614 is formed using a positive photosensitive acrylic resin. In this embodiment, the first electrode 613 is used as an anode.

The insulator 614 preferably has a curved surface having a curvature at its upper end or lower end. Thereby, the coating property of the film|membrane formed on the insulator 614 becomes favorable. The insulator 614 can be formed using, for example, either a negative photosensitive resin or a positive photosensitive resin. The material of the insulator 614 is not limited to an organic compound, and an inorganic compound such as silicon oxide, silicon oxynitride, or silicon nitride can also be used.

An EL layer 615 and a second electrode (cathode) 616 are formed on the first electrode (anode) 613 . The EL layer 615 includes at least a light emitting layer. The EL layer 615 may be suitably provided with a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a charge generation layer, and the like in addition to the light emitting layer.

The light emitting element 617 is formed by lamination of a first electrode (anode) 613 , an EL layer 615 , and a second electrode (cathode) 616 . The material described in Embodiment 1 can be used for the first electrode (anode) 613 , the EL layer 615 , and the second electrode (cathode) 616 . Although not shown, the second electrode (cathode) 616 is electrically connected to the FPC 608 which is an external input terminal.

Although only one light emitting element 617 is illustrated in the cross-sectional view of FIG. 6B , a plurality of light emitting elements are arranged in a matrix in the pixel portion 602 . A light-emitting device capable of full-color display can be manufactured by selectively forming light-emitting elements providing three types of light emission (R, G, and B) in the pixel portion 602 . In addition to the light emitting element providing three types of light emission (R, G, and B), for example, a light emitting element emitting light of white (W), yellow (Y), magenta (M), and cyan (C) is provided. may be formed. Providing the above-described light emitting device providing several types of light in addition to the light emitting device providing three types of light emission (R, G, and B) provides, for example, higher color purity and lower power consumption. etc can be realized. Alternatively, a light emitting device capable of full color display by combination of color filters may be provided. A light emitting device may be obtained in which luminous efficiency is improved and power consumption is reduced by combining with quantum dots.

Further, by bonding the sealing substrate 606 to the element substrate 601 with the sealant 605 , the light emitting element 617 is placed in the space 618 surrounded by the element substrate 601 , the sealing substrate 606 , and the sealant 605 . ) is provided. Further, the space 618 may be filled with an inert gas (such as nitrogen or argon) or a sealant 605 .

It is preferable to use an epoxy-based resin or glass frit for the sealant 605 . It is desirable that this material be permeable to moisture and oxygen as little as possible. As the sealing substrate 606, any material described in Embodiment 3 is used, such as a glass substrate, a quartz substrate, or a plastic substrate formed of FRP (fiber-reinforced plastic), PVF (polyvinyl fluoride), polyester, or acrylic. The formed substrate can be used. When a glass frit is used as the sealant, it is preferable to use the element substrate 601 and the sealing substrate 606 as glass substrates because the adhesive strength increases.

As described above, an active matrix light emitting device can be obtained.

In addition, the structure described in this embodiment can be used in appropriate combination with any structure described in other embodiment.

(Embodiment 5)

In this embodiment, (A), (B), (C), (D), (D'-1) of Figs. 7 for examples of various electronic devices manufactured using the light emitting device of one embodiment of the present invention , and (D'-2).

Examples of electronic devices including light emitting devices include television devices (also called TVs or television receivers), monitors for computers, etc., cameras such as digital cameras and digital video cameras, digital picture frames, and mobile phones (also called mobile phones or mobile phone devices). ), portable game machines, portable information terminals, audio reproducing devices, and large game machines such as pachinkogi. Specific examples of electronic devices are shown in (A), (B), (C), (D), (D'-1), and (D'-2) of FIG. 7 .

Fig. 7A shows an example of a television device. In the television device 7100 , a display portion 7103 is provided in a housing 7101 . The display unit 7103 may display an image and may be a touch panel (input/output device) including a touch sensor (input device). In addition, the light emitting device of one embodiment of the present invention can be used for the display unit 7103 . Here, the housing 7101 is supported by a stand 7105 .

The television device 7100 may be operated with an operation switch of the housing 7101 or a separate remote controller 7110 . A channel and a volume may be controlled with the operation key 7109 of the remote controller 7110 , and an image displayed on the display unit 7103 may be controlled. Further, the remote control 7110 may be provided with a display unit 7107 for displaying data output from the remote control 7110 .

In addition, the television device 7100 is provided with a receiver, a modem, and the like. A receiver can be used to receive general television broadcasts. In addition, when the television apparatus is connected to a wired or wireless communication network via a modem, information communication can be performed unidirectional (sender to receiver) or bidirectional (between sender and receiver or between receivers).

FIG. 7B shows a computer including a main body 7201 , a housing 7202 , a display unit 7203 , a keyboard 7204 , an external connection port 7205 , and a pointing device 7206 , and the like. In addition, this computer can be manufactured by using the light emitting device of one embodiment of the present invention for the display unit 7203 . The display unit 7203 may be a touch panel (input/output device) including a touch sensor (input device).

7C is a smart watch including a housing 7302 , a display panel 7304 , operation buttons 7311 and 7312 , connection terminals 7313 , a band 7321 , and a clasp 7322 , etc. will show

A display panel 7304 mounted on a housing 7302 serving as a bezel includes a non-rectangular display area. The display panel 7304 may display an icon 7305 indicating the time and other icons 7306 and the like. The display panel 7304 may be a touch panel (input/output device) including a touch sensor (input device).

The smart watch shown in FIG. 7C may have various functions, for example, a function of displaying various information (eg, still images, moving pictures, and text images) on the display unit, a touch panel function, a calendar , date, time, etc., function to control processing by various software (programs), wireless communication function, function to connect to various computer networks by wireless communication function, transmit various data by wireless communication function and a function of receiving and reading the program or data stored in the recording medium and displaying the program or data on the display unit.

Housing 7302 is a speaker, sensor (force, displacement, position, speed, acceleration, angular velocity, rotation frequency, distance, light, liquid, magnetism, temperature, chemical, voice, time, hardness, electric field, current) , voltage, power, radiation, flow rate, humidity, inclination, vibration, odor, or a sensor having a function of measuring infrared rays), and a microphone and the like. Also, a smart watch may be manufactured by using a light emitting device for the display panel 7304 .

7D shows an example of a mobile phone (eg, a smart phone). The mobile phone 7400 includes a housing 7401 provided with a display portion 7402, a microphone 7406, a speaker 7405, a camera 7407, an external connection portion 7404, and operation buttons 7403 and the like. When a light emitting device is manufactured by forming the light emitting device according to one embodiment of the present invention on a flexible substrate, the light emitting device can be used in the display portion 7402 having a curved surface as shown in FIG. 7D .

When the display unit 7402 of the mobile phone 7400 shown in FIG. 7D is touched with a finger or the like, data can be input into the mobile phone 7400 . In addition, operations such as making a call or writing an e-mail can be performed by touching the display unit 7402 with a finger or the like.

The display unit 7402 mainly has three screen modes. The first mode is a display mode mainly for displaying an image. The second mode is an input mode mainly for inputting data such as text. The third mode is a display and input mode in which two modes of a display mode and an input mode are combined.

For example, when making a phone call or writing an e-mail, a character input mode for mainly inputting characters may be selected for the display unit 7402, and characters displayed on the screen may be input. In this case, it is preferable to display the keyboard or number buttons on almost the entire screen of the display unit 7402 .

If a detection device such as a gyro sensor or an acceleration sensor is provided inside the mobile phone 7400, the direction of the mobile phone 7400 (whether the mobile phone is placed horizontally or vertically) is determined and the display unit 7402 is displayed. The screen display can be switched automatically.

The screen mode is switched by touching the display unit 7402 or operating a button 7403 of the housing 7401 . The screen mode can be changed according to the type of image displayed on the display unit 7402 . For example, if the signal of the image displayed on the display unit is moving picture data, the screen mode is changed to the display mode. If the signal is text data, the screen mode is changed to the input mode.

In addition, in the input mode, the screen mode is set to change from the input mode to the display mode if the display unit 7402 detects a signal detected by the optical sensor and a touch input is not performed on the display unit 7402 for a certain period of time. You may control it.

The display unit 7402 may function as an image sensor. For example, personal authentication can be performed by touching the display unit 7402 with a palm or a finger and taking an image such as a palm print or fingerprint. In addition, if a backlight emitting near-infrared light or a light source for sensing is provided on the display unit, an image of finger veins or palm veins can be taken.

In addition, the light emitting device can be used in a mobile phone having a structure shown in (D'-1) or (D'-2) of FIG. 7, which is another structure of a mobile phone (eg, a smart phone).

In addition, in the case of the structure shown in (D'-1) or (D'-2) of FIG. 7 , text data or image data is stored on the first screen 7501 of the housings 7500(1) and 7500(2). (1) and 7501(2)) as well as the second screens 7502(1) and 7502(2). With this structure, the user can easily view text data or image data displayed on the second screens 7502(1) and 7502(2) while putting the mobile phone in the user's breast pocket.

8A to 8C illustrate a foldable portable information terminal 9310 . FIG. 8A shows an unfolded portable information terminal 9310. As shown in FIG. FIG. 8B shows the portable information terminal 9310 being unfolded or folded. FIG. 8C shows a folded portable information terminal 9310. As shown in FIG. The portable information terminal 9310 is highly portable when folded. When the portable information terminal 9310 is unfolded, it is seamless and has high visibility due to the large display area.

The display panel 9311 is supported by three housings 9315 connected to each other by a hinge 9313 . In addition, the display panel 9311 may be a touch panel (input/output device) including a touch sensor (input device). By using the hinge 9313 to bend the display panel 9311 at the connection portion between the two housings 9315 , the portable information terminal 9310 can be reversibly deformed from an unfolded state to a folded state. The light emitting device according to one embodiment of the present invention can be used for the display panel 9311 . A display area 9312 of the display panel 9311 is a display area located on a side surface of the folded portable information terminal 9310 . In the display area 9312, information icons, frequently used applications, shortcuts to programs, etc. can be displayed, and information can be checked and applications can be started smoothly.

As described above, an electronic device can be obtained by applying the light emitting device of one embodiment of the present invention. In addition, the light emitting device is not limited to the electronic device described in the present embodiment, and can be used in electronic devices in various fields.

(Embodiment 6)

In the present embodiment, an example of a lighting device will be described with reference to FIG. 9 . Each lighting device uses the light emitting device of one embodiment of the present invention.

9 shows an example in which a light emitting device is used as the indoor lighting device 8001 . Since the light emitting device can have a large area, it can be used for a large area lighting device. Further, by using a housing having a curved surface, it is also possible to obtain a lighting device 8002 including a housing, a cover, or a support portion and having a light emitting area having a curved surface. The light emitting element included in the light emitting device described in this embodiment is in the form of a thin film, and thus it is possible to design the housing more freely. Accordingly, the lighting device can be designed in a sophisticated manner in various ways. In addition, a large-sized lighting device 8003 may be provided on the wall of the room.

If the light emitting device is used on the table surface, the lighting device 8004 having a function as a table can be obtained. If the light emitting device is used for a part of another piece of furniture, a lighting device that functions as the piece of furniture can be obtained.

As described above, various lighting devices including the light emitting device can be obtained. Moreover, these lighting devices are also one form of this invention.

In addition, the structure described in this embodiment can be used in appropriate combination with any structure described in other embodiment.

(Embodiment 7)

In the present embodiment, with respect to a touch panel including a light emitting element according to one embodiment of the present invention or a light emitting device according to one embodiment of the present invention, FIGS. 11A and 11B , and 12A and 12B ), FIGS. 13 (A) and (B), 14 (A) and (B), and FIG. 15 .

11A and 11B are perspective views of the touch panel 2000 . In addition, representative components of the touch panel 2000 are shown in FIGS. 11A and 11B for simplification.

The touch panel 2000 includes a display unit 2501 and a touch sensor 2595 (see FIG. 11B ). Also, the touch panel 2000 includes a substrate 2510 , a substrate 2570 , and a substrate 2590 . In addition, each of the substrate 2510 , the substrate 2570 , and the substrate 2590 has flexibility.

The display unit 2501 includes a plurality of pixels on a substrate 2510 and a plurality of wires 2511 for supplying signals to the pixels. The plurality of wirings 2511 are led to the outer periphery of the substrate 2510 , and a part of the plurality of wirings 2511 forms a terminal 2519 . Terminal 2519 is electrically connected to FPC 2509(1).

The substrate 2590 includes a touch sensor 2595 and a plurality of wires 2598 electrically connected to the touch sensor 2595 . The plurality of wirings 2598 are led to the outer periphery of the substrate 2590 , and a part of the plurality of wirings 2598 forms the connection layer 2599 . Connection layer 2599 is electrically connected to FPC 2509(2). Also, in FIG. 11B , electrodes and wires of the touch sensor 2595 provided on the back side of the substrate 2590 are indicated by solid lines for clarity.

As the touch sensor 2595 , for example, a capacitive touch sensor may be used. Examples of capacitive touch sensors include surface capacitive touch sensors and projected capacitive touch sensors.

Examples of projection capacitive touch sensors are mainly magnetocapacitive touch sensors and mutual capacitive touch sensors with different driving methods. The use of a mutual capacitive touch sensor is preferable because a plurality of points can be simultaneously detected.

First, an example using the projected capacitive touch sensor will be described below with reference to FIG. 11B . In addition, in the case of the projection capacitive touch sensor, various sensors capable of detecting proximity or contact of a detection target such as a finger may be used.

The projected capacitive touch sensor 2595 includes an electrode 2591 and an electrode 2592 . The electrode 2591 is electrically connected to any one of the plurality of wirings 2598 , and the electrode 2592 is electrically connected to another one of the plurality of wirings 2598 . The electrodes 2592 each have a shape in which a plurality of quadrilaterals are arranged in one direction as shown in FIGS. It is connected to one edge of the quadrilateral. Similarly, the electrode 2591 has a shape in which a plurality of quadrilaterals are arranged in one direction, and one corner of the quadrilateral is connected to one corner of the other quadrilateral, but the direction in which the electrodes 2591 are connected is the electrodes 2592 . This is a direction intersecting with the connecting direction. In addition, the direction in which the electrodes 2591 are connected and the direction in which the electrodes 2592 are connected are not necessarily perpendicular to each other, and the electrodes 2591 are positioned at an angle greater than 0° and less than 90°. ) may be arranged so as to intersect.

It is preferable that the crossing area of the wiring 2594 and one of the electrodes 2592 be as small as possible. With this structure, it is possible to reduce the area of the region where the electrode is not provided, thereby reducing the non-uniformity of transmittance. As a result, variations in the luminance of light from the touch sensor 2595 can be reduced.

In addition, the shape of the electrode 2591 and the electrode 2592 is not limited to the above-mentioned shape, It can be made into any of various shapes. For example, the plurality of electrodes 2591 are arranged so that the space between the electrodes 2591 is as small as possible, and an insulating layer is interposed between the electrodes 2591 and the electrodes 2592 . may be provided. In this case, it is preferable to provide a dummy electrode electrically insulated from the two adjacent electrodes 2592 between the two electrodes 2592 , since the area of regions having different transmittances can be reduced.

Next, the touch panel 2000 will be described in detail with reference to FIGS. 12A and 12B . 12A is a cross-sectional view taken along the dash-dotted line X1-X2 of FIG. 11A .

The touch sensor 2595 includes an electrode 2591 and an electrode 2592 provided in a staggered form on a substrate 2590 , an insulating layer 2593 covering the electrode 2591 and the electrode 2592 , and adjacent electrodes 2591 . and wiring 2594 for electrically connecting to each other.

An adhesive layer 2597 is provided under the wiring 2594 . The substrate 2590 is bonded to the substrate 2570 by the adhesive layer 2597 , and the touch sensor 2595 overlaps the display unit 2501 .

The electrode 2591 and the electrode 2592 are formed using a light-transmitting conductive material. As the light-transmitting conductive material, conductive oxides such as indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, or zinc oxide to which gallium is added can be used. Moreover, you may use the film|membrane containing graphene. The film containing graphene can be formed by reducing the film containing graphene oxide, for example. As the reduction method, a method of applying heat or the like can be employed.

For example, the electrode 2591 and the electrode 2592 may be formed by depositing a light-transmitting conductive material on the substrate 2590 by sputtering and then removing unnecessary portions by any of various patterning techniques such as photolithography. good night.

Examples of the material of the insulating layer 2593 include a resin such as acrylic or epoxy resin, a resin having a siloxane bond, and an inorganic insulating material such as silicon oxide, silicon oxynitride, or aluminum oxide.

The adjacent electrodes 2591 are electrically connected to each other by forming the wiring 2594 in the opening provided in the insulating layer 2593 . Since the translucent conductive material can increase the aperture ratio of the touch panel, it can be preferably used for the wiring 2594 . In addition, a material having higher conductivity than the electrodes 2591 and 2592 can be preferably used for the wiring 2594 because the electrical resistance can be reduced.

The pair of electrodes 2591 are electrically connected to each other via a wiring 2594 . An electrode 2592 is provided between the pair of electrodes 2591 .

One wiring 2598 is electrically connected to any of the electrodes 2591 and 2592 . A part of the wiring 2598 functions as a terminal. The wiring 2598 includes a metal material such as aluminum, gold, platinum, silver, nickel, titanium, tungsten, chromium, molybdenum, iron, cobalt, copper, or palladium, or an alloy material containing any of these metal materials. Can be used.

The wiring 2598 and the FPC 2509 ( 2 ) are electrically connected to each other via the connection layer 2599 . The connection layer 2599 may be formed using any one of various types of anisotropic conductive film (ACF) and anisotropic conductive paste (ACP).

The adhesive layer 2597 has light-transmitting properties. For example, a thermosetting resin or an ultraviolet curable resin may be used, and specifically, an acrylic resin, a urethane-based resin, an epoxy-based resin, or a siloxane-based resin may be used.

The display unit 2501 includes a plurality of pixels arranged in a matrix. The pixels each include a display element and a pixel circuit for driving the display element.

For the substrate 2510 and the substrate 2570 , for example, a flexible material having a water vapor transmittance of 10 ^-5 g/(m ² ·day) or less, preferably 10 ^-6 g/(m ² ·day) or less, is preferably used. can be used In addition, it is preferable to use materials having substantially the same coefficient of thermal expansion for the substrate 2510 and the substrate 2570 . For example, the coefficient of linear expansion of the material is preferably 1×10 ^-3 /K or less, more preferably 5×10 ^-5 /K or less, still more preferably 1×10 ^-5 /K or less.

The sealing layer 2560 preferably has a refractive index greater than that of air.

The display unit 2501 includes a pixel 2502R. Pixel 2502R includes a light emitting module 2580R.

The pixel 2502R includes a light emitting element 2550R, and a transistor 2502t capable of supplying power to the light emitting element 2550R. In addition, the transistor 2502t functions as a part of the pixel circuit. The light emitting module 2580R includes a light emitting element 2550R and a coloring layer 2567R.

The light emitting element 2550R includes a lower electrode, an upper electrode, and an EL layer between the lower electrode and the upper electrode.

When the sealing layer 2560 is provided on the light extraction side, the sealing layer 2560 is in contact with the light emitting element 2550R and the colored layer 2567R.

The colored layer 2567R overlaps the light emitting element 2550R. Accordingly, a portion of the light emitted from the light emitting device 2550R passes through the colored layer 2567R and is emitted to the outside of the light emitting module 2580R as indicated by an arrow in FIG. 12A .

The display unit 2501 includes a light blocking layer 2567BM on the light extraction side. A light blocking layer 2567BM is provided to surround the coloring layer 2567R.

The display unit 2501 includes an anti-reflection layer 2567p in an area overlapping the pixel. As the antireflection layer 2567p, for example, a circularly polarizing plate can be used.

An insulating layer 2521 is provided on the display unit 2501 . An insulating layer 2521 covers the transistor 2502t. The insulating layer 2521 flattens the unevenness resulting from the pixel circuit. The insulating layer 2521 may function as a layer for preventing diffusion of impurities. Accordingly, it is possible to prevent deterioration of reliability of the transistor 2502t and the like due to diffusion of impurities.

The light emitting device 2550R is formed on the insulating layer 2521 . A partition 2528 is provided to cover the end of the lower electrode of the light emitting element 2550R. Further, a spacer for controlling the distance between the substrate 2510 and the substrate 2570 may be provided on the partition 2528 .

The scan line driver circuit 2503g(1) includes a transistor 2503t and a capacitor 2503c. In addition, the driving circuit and the pixel circuit may be formed on the same substrate in the same process.

A wiring 2511 capable of supplying a signal is provided on the substrate 2510 . A terminal 2519 is provided over the wiring 2511 . FPC 2509 ( 1 ) is electrically connected to terminal 2519 . The FPC 2509(1) has a function of supplying signals such as a pixel signal and a synchronization signal. In addition, a printed wiring board (PWB) may be attached to the FPC 2509(1).

Transistors of various structures may be used for the display unit 2501 . In the example of Fig. 12A, a bottom gate transistor is used. In each of the transistor 2502t and the transistor 2503t shown in FIG. 12A, a semiconductor layer including an oxide semiconductor can be used for the channel region. Alternatively, in each of the transistors 2502t and 2503t, a semiconductor layer including amorphous silicon may be used for the channel region. Alternatively, in each of the transistors 2502t and 2503t, a semiconductor layer containing polycrystalline silicon obtained by crystallization treatment such as laser annealing can be used for the channel region.

12B shows the structure of the display unit 2501 using a top gate transistor.

In the case of a top-gate transistor, in addition to the above-mentioned semiconductor layer that can be used for a bottom-gate transistor, a semiconductor layer including polycrystalline silicon or a single-crystal silicon film displaced from a single-crystal silicon substrate or the like may be used for the channel region.

Next, a touch panel having a structure different from that shown in FIGS. 12A and 12B will be described with reference to FIGS. 13A and 13B.

13A and 13B are cross-sectional views of the touch panel 2001 . In the touch panel 2001 shown in FIGS. 13A and 13B , the relative position of the touch sensor 2595 with respect to the display unit 2501 is the touch panel shown in FIGS. 12A and 12B . (2000) is different. Hereinafter, different structures will be described in detail, and for other similar structures, reference may be made to the above-described description of the touch panel 2000 .

The colored layer 2567R overlaps the light emitting element 2550R. Further, the light emitting element 2550R shown in FIG. 13A emits light to the side where the transistor 2502t is provided. Accordingly, a portion of the light emitted from the light emitting device 2550R passes through the colored layer 2567R and is emitted to the outside of the light emitting module 2580R as indicated by an arrow in FIG. 13A .

The display unit 2501 includes a light blocking layer 2567BM on the light extraction side. A light blocking layer 2567BM is provided to surround the coloring layer 2567R.

The touch sensor 2595 is provided on the substrate 2510 side of the display unit 2501 (see FIG. 13A ).

The display unit 2501 and the touch sensor 2595 are bonded to each other with an adhesive layer 2597 provided between the substrate 2510 and the substrate 2590 .

Transistors of various structures may be used for the display unit 2501 . In the example of FIG. 13A, a bottom gate transistor is used. In the example of FIG. 13B, a top gate transistor is used.

Next, an example of a driving method of the touch panel will be described with reference to FIGS. 14A and 14B .

14A is a block diagram illustrating the structure of a mutual capacitive touch sensor. 14A shows a pulse voltage output circuit 2601 and a current detection circuit 2602 . Further, in the example of FIG. 14A , the six wirings X1-X6 represent the electrodes 2621 to which the pulse voltage is supplied, and the six wirings Y1-Y6 are the electrodes 2622 for detecting a change in current. ) is indicated. FIG. 14A also shows a capacitor 2603 formed in a region where the electrodes 2621 and 2622 overlap each other. Also, functional substitution between electrodes 2621 and 2622 is possible.

The pulse voltage output circuit 2601 is a circuit for sequentially applying a pulse voltage to the wirings X1 to X6. An electric field is generated between the electrodes 2621 and 2622 of the capacitor 2603 by applying a pulse voltage to the wirings X1 to X6. When the electric field between the electrodes is shielded, for example, a change occurs in capacitor 2603 (mutual capacitance). This change can be used to detect the proximity or contact of the detection target.

The current detection circuit 2602 is a circuit for detecting a change in current flowing through the wirings Y1 to Y6 due to a change in mutual capacitance in the capacitor 2603 . If there is no proximity or contact of the detection target, no change in the current value is detected in the wirings Y1 to Y6, but a decrease in the current value is detected when the mutual capacitance is reduced by the proximity or contact of the detection target. In addition, an integrating circuit or the like is used to detect the current value.

FIG. 14B is a timing chart showing input/output waveforms of the mutual capacitive touch sensor shown in FIG. 14A. In Fig. 14B, detection of the detection target is performed in all matrices in one frame period. Fig. 14B shows a period in which the detection object is not detected (non-touch) and a period in which the detection object is detected (touch). Current values of the detected wirings Y1 to Y6 are shown as voltage waveforms.

Pulse voltages are sequentially applied to the wirings X1 to X6, and the waveforms of the wirings Y1 to Y6 are changed according to the pulse voltage. When there is no proximity or contact with the detection target, the waveform of the wirings Y1 to Y6 changes according to the change in voltage of the wirings X1 to X6. Since the current value is reduced at the point where the detection target approaches or comes into contact, the waveform of the voltage value changes accordingly. By detecting the change in the mutual capacitance in this way, the proximity or contact of the detection target can be detected.

14A is a passive touch sensor in which only a capacitor 2603 is provided at the intersection of wirings as a touch sensor, but an active touch sensor including a transistor and a capacitor may be used. 15 is a sensor circuit included in an active touch sensor.

The sensor circuit shown in FIG. 15 includes a capacitor 2603 , a transistor 2611 , a transistor 2612 , and a transistor 2613 .

A signal G2 is input to the gate of the transistor 2613 . A voltage VRES is applied to one of the source and drain of the transistor 2613 , and one electrode of the capacitor 2603 and the gate of the transistor 2611 are electrically connected to the other of the source and the drain of the transistor 2613 . One of the source and the drain of the transistor 2611 is electrically connected to one of the source and the drain of the transistor 2612 , and a voltage VSS is applied to the other of the source and the drain of the transistor 2611 . A signal G1 is input to the gate of the transistor 2612 , and a wiring ML is electrically connected to the other of the source and the drain of the transistor 2612 . A voltage VSS is applied to the other electrode of the capacitor 2603 .

Next, the operation of the sensor circuit shown in Fig. 15 will be described. First, a potential for turning on the transistor 2613 is supplied as a signal G2, and a potential corresponding to the voltage VRES is applied to the node n connected to the gate of the transistor 2611. Then, a potential for turning off the transistor 2613 is applied as a signal G2, and the potential of the node n is maintained. Subsequently, as the mutual capacitance of the capacitor 2603 changes due to proximity or contact with an index target such as a finger, the potential of the node n changes in VRES.

In the read operation, a potential for turning on the transistor 2612 is supplied as a signal G1. The current flowing through the transistor 2611, that is, the current flowing through the wiring ML, changes according to the potential of the node n. By detecting this current, the proximity or contact of the detection target can be detected.

In each of the transistors 2611, 2612, and 2613, it is preferable to use an oxide semiconductor layer as the semiconductor layer in which the channel region is formed. In particular, using such a transistor as the transistor 2613 is preferable because the potential of the node n can be maintained for a long period of time and the frequency of the operation (refresh operation) of re-supplying VRES to the node n can be reduced.

At least a part of this embodiment may be practiced in appropriate combination with any of the embodiments described herein.

(Example 1)

In this embodiment, the calculation result of power consumption of a light emitting device performing white display will be described. In the light-emitting device of the present invention, a light-emitting element (yellow light-emitting element: light-emitting element 1, blue light-emitting element: light-emitting element 2, and green light-emitting element: light-emitting element 3) was used. For the light emitting device of the comparative example, a light emitting element (yellow light emitting element: comparative light emitting element 1, blue light emitting element: comparative light emitting element 2, and red light emitting element: comparative light emitting element 3) was used.

Light-emitting elements 1 to 3 are light-emitting elements emitting yellow light, blue light, and green light, respectively, and Comparative Light-emitting elements 1 to 3 are light-emitting elements emitting yellow light, blue light, and red light, respectively This is because light of this color is required to obtain white light with a chromaticity of about D65 (light whose chromaticity coordinates are ( x , y )=(0.313, 0.329) in the xy chromaticity diagram). Incidentally, in the light emitting device of this embodiment, red light is not required to obtain white light, and in the light emitting device of Comparative Example, green light is not required to obtain white light, and therefore the description thereof is omitted.

Structural formulas of the organic compounds used in the light-emitting devices 1 to 3 and comparative light-emitting devices 1 to 3 are shown below.

(Method of manufacturing light emitting devices 1 to 3 and comparative light emitting devices 1 to 3)

First, an alloy film of silver (Ag), palladium (Pd), and copper (Cu) (hereinafter referred to as APC) was formed on a glass substrate by sputtering to form a first electrode (reflecting electrode). . The thickness of the first electrode was 100 nm and the electrode area was 2 mm x 2 mm.

Next, as a transparent conductive film, a film of indium tin oxide containing silicon oxide was formed on the first electrode by sputtering. The thickness of the transparent conductive film of the light emitting element 1 was 30 nm, the thickness of the transparent conductive film of the light emitting element 2 was 80 nm, and the thickness of the transparent conductive film of the light emitting element 3 was 30 nm. The thickness of the transparent conductive film of the comparative light emitting element 1 was 30 nm, the thickness of the transparent conductive film of the comparative light emitting element 2 was 60 nm, and the thickness of the transparent conductive film of the comparative light emitting element 3 was 60 nm.

Then, as a pretreatment for deposition of the organic compound layer, the surface of the substrate provided with the reflective electrode and the transparent conductive film was washed with water, baked at 200° C. for 1 hour, and then subjected to UV ozone treatment for 370 seconds.

Thereafter, the substrate was transferred to a vacuum deposition apparatus in which the pressure was reduced to about 10 ⁻⁴ Pa, and vacuum baking was performed at 170° C. for 30 minutes in a heating chamber of the vacuum deposition apparatus, and then the substrate was cooled for 30 minutes.

Then, the substrate was fixed to a substrate holder provided in the vacuum vapor deposition apparatus so that the side on which the transparent conductive film was formed was facing downward. The pressure of the vacuum deposition apparatus was reduced to about 10 ^-4 Pa. Then, on the transparent conductive film, 3-[4-(9-phenanthryl)-phenyl]-9-phenyl-9 represented by the structural formula (i) by co-evaporation using resistance heating. A first hole injection layer was formed by depositing H -carbazole (abbreviation: PCPPn) and molybdenum (VI) oxide. The thickness of the first hole injection layer of the light emitting element 1 was 60 nm, the thickness of the first hole injection layer of the light emitting element 2 was 47.5 nm, and the thickness of the first hole injection layer of the light emitting element 3 was 40 nm. The thickness of the first hole injection layer of Comparative Light-Emitting Device 1 was 55 nm, the thickness of the first hole injection layer of Comparative Light-Emitting Device 2 was 70 nm, and the thickness of the first hole injection layer of Comparative Light-Emitting Device 3 was 45 nm. The weight ratio of PCPPn to molybdenum oxide was adjusted to 1:0.5.

Next, PCPPn was deposited to a thickness of 10 nm on the first hole injection layer to form a first hole transport layer.

For each of the light emitting devices 1 to 3, 7-[4-(10-phenyl-9-anthryl)phenyl] -7H -dibenzo[ c , g represented by the structural formula (ii) on the first hole transport layer ]carbazole (abbreviation: cgDBCzPA) and N , N '-(pyrene-1,6-diyl)bis[(6, N -diphenylbenzo[ b ]naphtho[1,2] represented by structural formula (iii)) -d ]furan)-8-amine] (abbreviation: 1,6BnfAPrn-03) was deposited to a thickness of 25 nm so that the weight ratio of cgDBCzPA to 1,6BnfAPrn-03 was 1:0.05 to form a first light emitting layer.

For each of Comparative Light-Emitting Devices 1 to 3, on the first hole transport layer, cgDBCzPA and N , N '-bis(3-methylphenyl) -N , N '-bis[3-(9-) represented by the structural formula (x) By depositing phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6mMemFLPAPrn ) to a thickness of 25 nm so that the weight ratio of cgDBCzPA to 1,6mMemFLPAPrn is 1:0.05 A first light emitting layer was formed.

Then, a first electron transport layer was formed on the first light emitting layer by depositing cgDBCzPA to a thickness of 5 nm and depositing vasophenanthroline (abbreviation: BPhen) represented by the structural formula (iv) to a thickness of 15 nm.

After forming the first electron transport layer, lithium oxide (Li ₂ O) was deposited to a thickness of 0.1 nm. Then, copper phthalocyanine (abbreviation: CuPc) represented by the structural formula (xi) was deposited to a thickness of 2 nm. Then, 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviation: DBT3P-II) and molybdenum oxide represented by the structural formula (v) (VI) was co-deposited so that the weight ratio of DBT3P-II to molybdenum oxide was 1:0.5. In this way, an intermediate layer was formed. The thickness of the intermediate layer was 12.5 nm.

Next, on the intermediate layer, 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP) represented by the structural formula (vi) was deposited to a thickness of 20 nm to form a second hole transport layer was formed.

After forming the second hole transport layer, 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[ f , h ]quinoxaline (abbreviated as : 2mDBTBPDBq-II), N- (1,1'-biphenyl-4-yl)-9,9-dimethyl- N- [4-(9-phenyl-9H- carba ) represented by the structural formula (viii) zol-3-yl)phenyl]-9H-fluoren-2-amine (abbreviation: PCBBiF ), and bis{2-[5-methyl-6-(2-methylphenyl)-4 represented by the structural formula (ix) -pyrimidinyl-κ N 3]phenyl-κ C } (2,4-pentanedionato-κ ² O , O ′) iridium (III) (abbreviation: [Ir(mpmppm) ₂ (acac)]) was co-deposited so that the weight ratio of 2mDBTBPDBq-II to PCBBiF and [Ir(mpmppm) ₂ (acac)] was 0.8:0.2:0.06. In this way, a second light emitting layer was formed. The thickness of the second light emitting layer was 40 nm.

Then, on the second light emitting layer, 2mDBTBPDBq-II was deposited to a thickness of 15 nm. For each of the light-emitting devices 1 to 3, BPhen was further deposited to a thickness of 20 nm. For each of Comparative Light-Emitting Devices 1 to 3, BPhen was further deposited to a thickness of 15 nm. In this way, a second electron transport layer was formed.

Thereafter, lithium fluoride was deposited to a thickness of 1 nm to form an electron injection layer. Then, silver and magnesium were co-deposited with a thickness of 15 nm and a volume ratio of 1:0.1 (=silver:magnesium). Next, ITO was deposited to a thickness of 70 nm by sputtering. In this way, the second electrode (semi-transmissive/semi-reflective electrode) was formed. Through the above-described steps, light emitting devices 1 to 3 and comparative light emitting devices 1 to 3 were manufactured. In addition, in all the above-mentioned vapor deposition steps, vapor deposition was performed by the resistance heating method.

The device structures of the light-emitting devices 1 to 3 and comparative light-emitting devices 1 to 3 are listed below.

[Table 1]

^* 1 Light emitting element 1 to 3: 1,6BnfAPrn-03

Comparative light emitting devices 1 to 3: 1,6mMemFLPAPrn

^* 2 Light emitting element 1 and comparative light emitting element 1: 0.8 μm

Light emitting element 2 and comparative light emitting element 2: blue 0.8 μm

Light emitting element 3: Green 1.3 µm, Comparative light emitting element 3: Red 2.4 µm

^* 3 Light-emitting element 1: 30 nm, Light-emitting element 2: 80 nm, Light-emitting element 3: 30 nm

Comparative light emitting device 1: 30 nm, Comparative light emitting device 2: 60 nm, Comparative light emitting device 3: 60 nm

^* 4 Light emitting element 1: 60 nm, Light emitting element 2: 47.5 nm, Light emitting element 3: 40 nm

Comparative light emitting device 1: 55 nm, Comparative light emitting device 2: 70 nm, Comparative light emitting device 3: 45 nm

^* 5 Light emitting elements 1 to 3: 20 nm

Comparative light emitting devices 1 to 3: 15 nm

Light-emitting elements 1 to 3 and comparative light-emitting elements 1 to 3 were each sealed using a glass substrate in a glove box containing a nitrogen atmosphere so as not to be exposed to the atmosphere (specifically, a sealing material was applied to surround the element and , UV treatment (UV light 365nm, 6J/cm ² ) was performed at the time of sealing, and heat treatment was performed at 80° C. for 1 hour). Then, the initial characteristics of these light emitting devices were measured. In addition, the measurement was performed at room temperature (atmosphere maintained at 25 degreeC).

Fig. 16 shows the luminance-current density characteristics of the light emitting devices 1 to 3, Fig. 17 shows the current efficiency-luminance characteristics thereof, Fig. 18 shows the luminance-voltage characteristics thereof, and Fig. 19 shows the current-voltage characteristics. characteristics, and FIG. 20 shows the chromaticity coordinates thereof.

21 shows the luminance-current density characteristics of Comparative Light-Emitting Devices 1 to 3, FIG. 22 shows the current efficiency-luminance characteristics thereof, FIG. 23 shows the luminance-voltage characteristics thereof, and FIG. 24 shows the current- Voltage characteristics are shown, and FIG. 25 shows the chromaticity coordinates thereof.

As shown in FIGS. 20 and 25 , the light emitting device 2 including 1,6BnfAPrn-03 has chromaticity coordinates ( x , y )=(0.152, 0.037) in the vicinity of 1000 cd/m ² , and comparison including 1,6mMemFLPAPrn Light emitting element 2 has a chromaticity coordinate of ( x , y )=(0.160, 0.087). This indicates that light-emitting element 2 exhibits a deeper blue emission than comparative light-emitting element 2.

26 shows the emission spectrum of 1,6BnfAPrn-03 in toluene solution of 1,6BnfAPrn-03. As can be seen from FIG. 26, the peak wavelength of the emission spectrum of 1,6BnfAPrn-03 in toluene solution was 450 nm. The half width of the emission spectrum was 40 nm. On the other hand, the peak wavelength of 1,6mMemFLPAPrn in the toluene solution used for the comparative light emitting element was 461 nm.

Next, the power consumption of the light emitting device including the light emitting element when obtaining white light having a chromaticity of about D65 was calculated. The power consumption of the light emitting device was calculated under the following conditions.

[Table 2]

Table 3 shows the calculation results of the light emitting device of this example, and Table 4 shows the calculation results of the light emitting device of the comparative example.

[Table 3]

[Table 4]

In the above calculation result, the effective luminance is the intrinsic luminance x the aperture ratio x 1/4 (area ratio of each sub-pixel (assuming that one pixel in the light emitting device includes four sub-pixels of red, green, blue, and yellow)) was obtained from the calculation of ; The amount of current was obtained from the calculation of current density x panel area x aperture ratio x 1/4 (area ratio of each sub-pixel); The power consumption of the display part was obtained from the calculation of the amount of current x voltage.

As can be seen from Tables 3 and 4, the luminance of blue light emission required to obtain white light having a chromaticity of about D65 of the light emitting device of the present Example (light emission of light emitting element 2) is as low as 15 cd/m ² , but the light emission of Comparative Example The luminance of blue light emission required to obtain white light having a chromaticity of about D65 of the device (light emission of the comparative light-emitting element 2) was 38 cd/m ² . This is because by using 1,6BnfAPrn-03, which is a fluorescent substance as described in Embodiments 1 and 2, as a blue light emitting material, the chromaticity of blue light emission is improved, and the effective luminance of blue light required for white light is reduced. . Accordingly, the power consumption of the light emitting element 2 required to obtain white light is significantly reduced.

The power consumption of the light emitting element 3 required to obtain white light with a chromaticity of about D65 was as low as 22.7 mW, but the power consumption of the comparative light emitting element 3 required to obtain white light with a chromaticity of about D65 was 39.1 mW. This also indicates that the power consumption of the light emitting device of this embodiment is lower.

The reason for this is as follows: since deep blue light emission is obtained from light emitting element 2, the luminescence color obtained by combining blue light emission and yellow light emission of light emitting element 1 is different, and the third necessary for obtaining white light having a chromaticity of about D65 is different. The color of the light has changed. In the light emitting device of this embodiment, green light emission was required as the third light emission. On the other hand, in the light emitting device of the comparative example, red light emission was required as the third light emission. The ratio of the luminance of green light required to obtain white light of the light emitting device of this embodiment is higher than the ratio of the luminance of red light required for obtaining white light of the light emitting device of the comparative example.

However, since the visibility of green light emission is higher than that of red light emission, the current efficiency of light emitting element 3 exhibiting green light emission is about twice that of comparative light emission element 3 exhibiting red light emission. Therefore, in the light emitting device of this embodiment, even when the ratio of the luminance of the third light emission (light emission of the light emitting element 3) necessary to obtain white light is increased, the power consumption of the light emitting element 3 can be made lower than that of the comparative light emitting element 3 .

In the light emitting device of this embodiment, the effective luminance of the light emitting device 2 (blue) and the effective luminance of the light emitting device 3 (green) required to obtain white light having a chromaticity of about D65 at a luminance of 300 cd/m ² are, respectively, the light emitting device of the comparative example Although the effective luminance of comparative light emitting element 2 (blue) and the effective luminance of comparative light emitting element 3 (red) required to obtain white light with a chromaticity of about D65 at a luminance of 300 cd/m ² , this deficiency is lower than that of light emitting element 1 It can be compensated by the high luminance of yellow light emission. Since the current efficiency of the light emitting device 1 exhibiting yellow light emission is remarkably high, an increase in power consumption due to an increase in required luminance can be offset by a decrease in luminance required for the light emitting device 2 and the light emitting device 3 . As a result, reduction in power consumption of the light emitting device of this embodiment can be realized.

As a result, in the light emitting device of this embodiment performing white display, the power consumption excluding the power consumption of the driving FET was 5.8 mW/cm ² , and the power consumption including the power consumption of the driving FET was 14 mW/cm ² . In the light emitting device of the comparative example performing white display, the power consumption excluding the power consumption of the driving FET was 7.1 mW/cm ² , and the power consumption including the power consumption of the driving FET was 16 mW/cm ² . The power consumption may be about 10% to 20% lower than the power consumption of the comparative example. In addition, the power consumption of the light emitting device including the driving FET was estimated on the assumption that the voltage between the anode and the cathode (the sum of the voltages of the light emitting element and the driving FET parts) was 15V.

Since the blue light emitting device consumes much higher power than other color light emitting devices, the effect of reducing power consumption due to the change in chromaticity is significant. Further, reduction in power consumption can be realized by changing the balance regarding the ratio of luminance and emission color to obtain white light having a chromaticity of about D65. As a result, the power consumption of the light emitting device of this embodiment containing the fluorescent substance as described in Embodiment 1 can be made low.

(Example 2)

In this embodiment, the result of calculating the power consumption of the light emitting device performing white display will be described. In the light-emitting device of the present invention, a light-emitting element (red light-emitting element: light-emitting element 4, yellow light-emitting element: light-emitting element 5, green light-emitting element: light-emitting element 6, and blue light-emitting element: light-emitting element 7) is used. In the light emitting device of the comparative example, a light emitting element (red light emitting element: comparative light emitting element 4, green light emitting element: comparative light emitting element 5, and blue light emitting element: comparative light emitting element 6) was used.

Structural formulas of the organic compounds used in the light-emitting devices 4 to 7 and comparative light-emitting devices 4 to 6 are shown below.

(Method of manufacturing light emitting devices 4 to 7 and comparative light emitting devices 4 to 6)

First, an alloy film of silver (Ag), palladium (Pd), and copper (Cu) (hereinafter referred to as APC) was formed on a glass substrate by sputtering to form a first electrode (reflecting electrode). . The thickness of the first electrode was 100 nm and the electrode area was 2 mm x 2 mm.

Next, as a transparent conductive film, a film of indium tin oxide containing silicon oxide was formed on the first electrode by sputtering. The thickness of the transparent conductive film of the light emitting element 4 (red) is 80 nm, the thickness of the transparent conductive film of the light emitting element 5 (yellow) is 45 nm, the thickness of the transparent conductive film of the light emitting element 6 (green) is 45 nm, and the light emitting element 7 (blue) is ), the thickness of the transparent conductive film was 80 nm. The thickness of the transparent conductive film of the comparative light emitting element 4 (red) was 85 nm, the thickness of the transparent conductive film of the comparative light emitting element 5 (green) was 45 nm, and the thickness of the transparent conductive film of the comparative light emitting element 6 (blue) was 110 nm.

Then, as a pretreatment for deposition of the organic compound layer, the surface of the substrate provided with the reflective electrode and the transparent conductive film was washed with water, baked at 200° C. for 1 hour, and then subjected to UV ozone treatment for 370 seconds.

Thereafter, the substrate was transferred to a vacuum deposition apparatus in which the pressure was reduced to about 10 ⁻⁴ Pa, and vacuum baking was performed at 170° C. for 30 minutes in a heating chamber of the vacuum deposition apparatus, and then the substrate was cooled for 30 minutes.

Then, the substrate was fixed to a substrate holder provided in the vacuum vapor deposition apparatus so that the side on which the transparent conductive film was formed was facing downward. The pressure of the vacuum deposition apparatus was reduced to about 10 ^-4 Pa. Then, 3-[4-(9-phenanthryl)-phenyl]-9-phenyl- 9H -carbazole ( A first hole injection layer was formed by depositing abbreviation: PCPPn) and molybdenum (VI) oxide. The thickness of the first hole injection layer of the light emitting element 4 (red) is 30 nm, the thickness of the first hole injection layer of the light emitting element 5 (yellow) is 40 nm, and the thickness of the first hole injection layer of the light emitting element 6 (green) is is 22.5 nm, and the thickness of the first hole injection layer of the light emitting element 7 (blue) was 50 nm. The thickness of the first hole injection layer of the comparative light emitting element 4 (red) is 10 nm, the thickness of the first hole injection layer of the comparative light emitting element 5 (green) is 10 nm, and the first hole injection of the comparative light emitting element 6 (blue) is The thickness of the layer was 15 nm. The weight ratio of PCPPn to molybdenum oxide was adjusted to 1:0.5.

Next, PCPPn was deposited on the first hole injection layer to form a first hole transport layer. The thickness of the first hole transport layer of each of the light emitting devices 4 to 7 was 10 nm, and the thickness of the first hole transport layer of each of the comparative light emitting devices 4 to 6 was 15 nm.

On the first hole transport layer, 7-[4-(10-phenyl-9-anthryl)phenyl]-7H-dibenzo[ c , g ]carbazole (abbreviation: cgDBCzPA ) represented by the structural formula (ii) and N , N '-(pyrene-1,6-diyl)bis[(6, N -diphenylbenzo[ b ]naphtho[1,2- d ]furan)-8-amine represented by the structural formula (iii) ] (abbreviation: 1,6BnfAPrn-03) was deposited to a thickness of 25 nm so that the weight ratio of cgDBCzPA to 1,6BnfAPrn-03 was 1:0.05 to form a first light emitting layer.

Then, a first electron transport layer was formed on the first light emitting layer by depositing cgDBCzPA to a thickness of 5 nm and depositing vasophenanthroline (abbreviation: BPhen) represented by the structural formula (iv) to a thickness of 15 nm.

After forming the first electron transport layer, lithium oxide (Li ₂ O) was deposited to a thickness of 0.1 nm. Then, copper phthalocyanine (abbreviation: CuPc) represented by the structural formula (xi) was deposited to a thickness of 2 nm. Then, 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviation: DBT3P-II) represented by the structural formula (v) and molybdate oxide It was co-deposited so that the weight ratio of DBT3P-II to molybdenum oxide was 1:0.5. In this way, an intermediate layer was formed. The thickness of the intermediate layer was 12.5 nm.

Next, on the intermediate layer, 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP) represented by the structural formula (vi) was deposited to a thickness of 20 nm to form a second hole transport layer was formed.

For each of the light emitting devices 4 to 7, after forming the second hole transport layer, 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo [ f , h ]quinoxaline (abbreviation: 2mDBTBPDBq-II), N- (1,1'-biphenyl-4-yl)-9,9-dimethyl- N- [4- represented by structural formula (viii) (9-phenyl-9H-carbazol-3-yl)phenyl]-9H-fluoren-2-amine (abbreviation: PCBBiF ), and bis { 2-[5-methyl- represented by the structural formula (ix) 6-(2-methylphenyl)-4-pyrimidinyl-κ N 3]phenyl-κ C } (2,4-pentanedionato-κ ² O , O ′) iridium (III) (abbreviation: [Ir (mpmppm) ₂ (acac)]) was co-deposited such that the weight ratio of 2mDBTBPDBq-II to PCBBiF and [Ir(mpmppm) ₂ (acac)] was 0.8:0.2:0.06. In this way, a second light emitting layer was formed. The thickness of the second light emitting layer was 40 nm.

For each of Comparative Light-Emitting Devices 4 to 6, after forming the second hole transport layer, 2mDBTBPDBq-II, PCBBiF, and bis[2-(6- tert -butyl-4-pyrimidinyl-) represented by the structural formula (xii)- κ N 3)phenyl-κC](2,4-pentanedioneto-κ ² O , O ′) iridium (III) (abbreviation: [Ir(tBuppm) ₂ (acac)]) was co-deposited to a thickness of 20 nm. did. Then, 2mDBTBPDBq-II and bis{4,6-dimethyl-2-[5-(2,6-dimethylphenyl)-3-(3,5-dimethylphenyl)-2-pyrazinyl- κN ]phenyl -κ C } (2,8-dimethyl-4,6-nonanedionato-κ ² O , O ' ) iridium (III) (abbreviation: [Ir(dmdppr-dmp) ₂ (divm)]), It was co-deposited to a thickness of 20 nm so that the weight ratio of 2mDBTBPDBq-II to [Ir(dmdppr-dmp) ₂ (divm)] was 1:0.06. In this way, a second light emitting layer was formed.

For each of the light-emitting elements 4 to 7, 2mDBTBPDBq-II was deposited to a thickness of 15 nm on the second light-emitting layer. For each of Comparative Light-Emitting Devices 4 to 6, 2mDBTBPDBq-II was deposited to a thickness of 30 nm on the second light-emitting layer. For each of the light emitting devices 4 to 7, BPhen was further deposited to a thickness of 20 nm on 2mDBTBPDBq-II. For each of Comparative Light-emitting Devices 4 to 6, BPhen was further deposited to a thickness of 15 nm on 2mDBTBPDBq-II. In this way, a second electron transport layer was formed.

Thereafter, lithium fluoride was deposited to a thickness of 1 nm to form an electron injection layer. Then, silver and magnesium were co-deposited with a thickness of 15 nm and a volume ratio of 1:0.1 (=silver:magnesium). Next, ITO was deposited to a thickness of 70 nm by sputtering. In this way, the second electrode (semi-transmissive/semi-reflective electrode) was formed. Through the above-described steps, light emitting devices 4 to 7 and comparative light emitting devices 4 to 6 were manufactured. In addition, in all the above-mentioned vapor deposition steps, vapor deposition was performed by the resistance heating method.

The device structures of the light-emitting devices 4 to 7 and comparative light-emitting devices 4 to 6 are listed below.

[Table 5]

^* 10 Light emitting element 4: 80 nm, Light emitting element 5: 45 nm, Light emitting element 6: 45 nm, Light emitting element 7: 80 nm

Comparative light emitting element 4: 85 nm, Comparative light emitting element 5: 45 nm, Comparative light emitting element 6: 110 nm

^* 11 Light emitting element 4: 30 nm, Light emitting element 5: 40 nm, Light emitting element 6: 22.5 nm, Light emitting element 7: 50 nm

Comparative light emitting element 4: 10 nm, Comparative light emitting element 5: 10 nm, Comparative light emitting element 6: 15 nm

^* 12 Light emitting elements 4 to 7: 10 nm, Comparative light emitting elements 4 to 6: 15 nm

^* 13 Light emitting elements 4 to 7

2mDBTBPDBq-II:PCBBiF:[Ir(mpmppm) ₂ (acac)]=0.8:0.2:0.06, 40nm

Comparative light emitting devices 4 to 6

2mDBTBPDBq-II:PCBBiF:[Ir(tBuppm) ₂ (acac)]=0.7:0.3:0.06, 20nm

+2mDBTBPDBq-II:[Ir(dmdppr-dmp) ₂ (divm)]=1:0.06, 20nm

^* 14 Light emitting element 4 to 7: 15 nm, Comparative light emitting element 4 to 6: 30 nm

^* 15 light emitting devices 4 to 7: 20 nm, comparative light emitting devices 4 to 6: 15 nm

^* 16 Light emitting element 4 and comparative light emitting element 4: Red 2.4 μm

Light emitting element 5: yellow 0.8 μm

Light emitting element 6 and comparative light emitting element 5: green 1.3 μm

Light emitting element 7 and comparative light emitting element 6: blue 0.8 μm

Light-emitting elements 4 to 7 and comparative light-emitting elements 4 to 6 were each sealed using a glass substrate in a glove box containing a nitrogen atmosphere so as not to be exposed to the atmosphere (specifically, a sealing material was applied to surround the element and , UV treatment (UV light 365nm, 6J/cm ² ) was performed at the time of sealing, and heat treatment was performed at 80° C. for 1 hour). Then, the initial characteristics of these light emitting devices were measured. In addition, the measurement was performed at room temperature (atmosphere maintained at 25 degreeC).

Fig. 28 shows the luminance-current density characteristics of the light emitting devices 4 to 7, Fig. 29 shows the current efficiency-luminance characteristics thereof, Fig. 30 shows the luminance-voltage characteristics thereof, and Fig. 31 shows the current-voltage characteristics. characteristics, and Fig. 32 shows the chromaticity coordinates thereof.

33 shows the luminance-current density characteristics of comparative light emitting devices 4 to 6, FIG. 34 shows their current efficiency-luminance characteristics, FIG. 35 shows their luminance-voltage characteristics, and FIG. 36 shows the current- voltage characteristics are shown.

Next, the power consumption for obtaining white light with a chromaticity of about D65 of the light emitting device including the light emitting element was calculated. The power consumption of the light emitting device was calculated under the following conditions.

[Table 6]

Table 7 shows the calculation results of the light emitting device of this example, and Table 8 shows the calculation results of the light emitting device of the comparative example.

[Table 7]

[Table 8]

In the above calculation result, the effective luminance is the intrinsic luminance x the aperture ratio x 1/4 (area ratio of each sub-pixel (assuming that one pixel in the light emitting device includes four sub-pixels of red, green, blue, and yellow)) was obtained from the calculation of ; The amount of current was obtained from the calculation of current density x panel area x aperture ratio x 1/4 (area ratio of each sub-pixel); The power consumption of the display part was obtained from the calculation of the amount of current x voltage.

As can be seen from Tables 7 and 8, the power consumption for obtaining white light of the light emitting device of this example was 266 mW, and the power consumption for obtaining white light of the light emitting device of Comparative Example was 394 mW. The device consumes less power than the comparative example. In the light emitting device of the comparative example, both the comparative light emitting element 4 (red) and the comparative light emitting element 5 (green) require a constant ratio of intrinsic luminance when emitting white light. On the other hand, in the light emitting device of this embodiment, when emitting white light, light emitting element 4 (red) does not emit light and light emitting luminance of light emitting element 6 (green) is as low as 139 cd/m ² , so they are consumed substantially. Does not affect power. That is, in the light emitting device of this embodiment, substantially only light emitting element 7 (blue) and light emitting element 5 (yellow) emit light when white light is emitted. Although the power consumption of the blue light emitting device of the light emitting devices of this embodiment and the comparative example is substantially the same, since the current efficiency of the light emitting device 5 (yellow) is as high as 137 cd/A, the power consumption of the light emitting device of this example is the same as that of the light emitting device of the comparative example. significantly lower than the device.

(Example 3)

The estimation result of luminance deterioration when the light emitting device according to one embodiment of the present invention performs white display with a chromaticity of about D65 at a luminance of 300 cd/m ² is shown. In this embodiment, under the condition that the current density is constant, the driving tests of the light emitting element 8 (blue) and the light emitting element 9 (yellow) having the same structure as the light emitting element of the light emitting device according to one embodiment of the present invention were conducted. The initial luminance of the light emitting element 8 was set to 300 cd/m ² , and the initial luminance of the light emitting element 9 was set to 3000 cd/m ² . These values are close to the luminance values necessary for performing white display with a chromaticity of about D65 in the light emitting device according to one embodiment of the present invention under the following conditions. The reason why the driving test was performed on the assumption that white display is performed is that it is necessary to continuously emit light for white display, and accordingly, the element deteriorates the fastest when performing white display.

[Table 9]

In addition, since light is extracted from the yellow light emitting layer, it is considered that a red light emitting element or a green light emitting element exhibits similar degradation behavior to that of a yellow light emitting element, and the red light emitting element and green light emitting element required for white display with a chromaticity of about D65. The luminance is low as described in Example 2, and since they do not affect reliability, no driving test was performed on the red light emitting element or the green light emitting element.

The structural formulas of the organic compounds used for the light-emitting elements 8 and 9 are shown below.

(Method of manufacturing light emitting elements 8 and 9)

First, an alloy film of silver (Ag), palladium (Pd), and copper (Cu) (hereinafter referred to as APC) was formed on a glass substrate by sputtering to form a first electrode (reflecting electrode). . The thickness of the first electrode was 100 nm and the electrode area was 2 mm x 2 mm.

Next, as a transparent conductive film, a film of indium tin oxide containing silicon oxide was formed on the first electrode by sputtering. The thickness of the transparent conductive film of the light emitting element 8 (blue) was 85 nm, and the thickness of the transparent conductive film of the light emitting element 9 (yellow) was 65 nm.

Then, as a pretreatment for deposition of the organic compound layer, the surface of the substrate provided with the reflective electrode and the transparent conductive film was washed with water, baked at 200° C. for 1 hour, and then subjected to UV ozone treatment for 370 seconds.

Thereafter, the substrate was transferred to a vacuum deposition apparatus in which the pressure was reduced to about 10 ⁻⁴ Pa, and vacuum baking was performed at 170° C. for 30 minutes in a heating chamber of the vacuum deposition apparatus, and then the substrate was cooled for 30 minutes.

Then, the substrate was fixed to a substrate holder provided in the vacuum vapor deposition apparatus so that the side on which the transparent conductive film was formed was facing downward. Then, on the transparent conductive film, 9-phenyl-3-[4-(10-phenyl-9-anthryl)phenyl] -9H- represented by the structural formula (xiv) by co-evaporation using resistance heating. A first hole injection layer was formed by depositing carbazole (abbreviated: PCzPA) and molybdenum (VI) oxide. The thickness of the first hole injection layer of the light emitting element 8 (blue) was 40 nm, and the thickness of the first hole injection layer of the light emitting element 9 (yellow) was 45 nm. The weight ratio of PCzPA to molybdenum oxide was adjusted to 1:0.5.

Next, PCzPA was deposited on the first hole injection layer to form a first hole transport layer. The thickness of the first hole transport layer was 20 nm.

On the first hole transport layer, 7-[4-(10-phenyl-9-anthryl)phenyl]-7H-dibenzo[ c , g ]carbazole (abbreviation: cgDBCzPA ) represented by the structural formula (ii) and N , N '-(pyrene-1,6-diyl)bis[(6, N -diphenylbenzo[ b ]naphtho[1,2- d ]furan)-8-amine represented by the structural formula (iii) ] (abbreviation: 1,6BnfAPrn-03) was deposited to a thickness of 25 nm so that the weight ratio of cgDBCzPA to 1,6BnfAPrn-03 was 1:0.03 to form a first light emitting layer.

Then, a first electron transport layer was formed on the first light emitting layer by depositing cgDBCzPA to a thickness of 10 nm and depositing vasophenanthroline (abbreviation: BPhen) represented by the structural formula (vi) to a thickness of 10 nm.

After forming the first electron transport layer, lithium oxide (Li ₂ O) was deposited to a thickness of 0.1 nm. Then, copper phthalocyanine (abbreviation: CuPc) represented by the structural formula (xi) was deposited to a thickness of 2 nm. Thereafter, PCzPA and molybdenum oxide were co-deposited so that the weight ratio of PCzPA to molybdenum oxide was 1:0.5. In this way, an intermediate layer was formed. The thickness of the intermediate layer was 12.5 nm.

Next, on the intermediate layer, a second hole transport layer was formed by vapor-depositing PCzPA to a thickness of 20 nm.

After forming the second hole transport layer, 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[ f , h ]quinoxaline (abbreviated as : 2mDBTBPDBq-II), N- (1,1'-biphenyl-4-yl)-9,9-dimethyl- N- [4-(9-phenyl-9H- carba ) represented by the structural formula (viii) zol-3-yl)phenyl]-9H-fluoren-2-amine (abbreviation: PCBBiF ), and bis{2-[5-methyl-6-(2-methylphenyl)-4 represented by the structural formula (ix) -pyrimidinyl-κ N 3]phenyl-κ C } (2,4-pentanedionato-κ ² O , O ′) iridium (III) (abbreviation: [Ir(mpmppm) ₂ (acac)]) was co-deposited so that the weight ratio of 2mDBTBPDBq-II to PCBBiF and [Ir(mpmppm) ₂ (acac)] was 0.8:0.2:0.06. In this way, a second light emitting layer was formed. The thickness of the second light emitting layer was 40 nm.

On the second light-emitting layer, 2mDBTBPDBq-II was deposited to a thickness of 15 nm. On 2mDBTBPDBq-II, BPhen was deposited to a thickness of 20 nm. In this way, a second electron transport layer was formed.

Thereafter, lithium fluoride was deposited to a thickness of 1 nm to form an electron injection layer. Then, silver and magnesium were co-deposited with a thickness of 15 nm and a volume ratio of 1:0.1 (=silver:magnesium). Next, ITO was deposited to a thickness of 70 nm by sputtering. In this way, the second electrode (semi-transmissive/semi-reflective electrode) was formed. Through the above-described steps, light emitting device 8 (blue) and light emitting device 9 (yellow) were manufactured. In addition, in all the above-mentioned vapor deposition steps, vapor deposition was performed by the resistance heating method.

The device structures of light-emitting devices 8 and 9 are listed below.

[Table 10]

^* 19 Light emitting element 8: 85 nm, Light emitting element 9: 65 nm

^* 20 Light emitting element 8: 40 nm, Light emitting element 9: 45 nm

^* 21 Light emitting element 8: blue 0.8 µm, light emitting element 9: yellow 0.8 µm

Light-emitting element 8 (blue) and light-emitting element 9 (yellow) were each sealed using a glass substrate in a glove box containing a nitrogen atmosphere so as not to be exposed to the atmosphere (specifically, a sealing material was applied to surround the element) and UV treatment (UV light 365 nm, 6J/cm ² ) at the time of sealing and heat treatment at 80° C. for 1 hour). Then, the initial characteristics of these light emitting devices were measured. In addition, the measurement was performed at room temperature (atmosphere maintained at 25 degreeC). For the light emitting element 8, the measurement was performed with respect to the light passing through the blue color filter. The light-emitting element 9 was measured for light passing through a yellow color filter.

Fig. 39 shows the luminance-current density characteristics of the light-emitting element 8 (blue) and the light-emitting element 9 (yellow), Fig. 40 shows the current efficiency-luminance characteristic, and Fig. 41 shows the luminance-voltage characteristic. , FIG. 42 shows its current-voltage characteristics, and FIG. 43 shows its emission spectrum. As shown in these graphs, the light-emitting element 8 and the light-emitting element 9 have good characteristics.

Next, the light-emitting element 8 (blue) and the light-emitting element 9 (yellow) are driven under the condition that the initial luminance of the light-emitting element 8 is 300 cd/m ² , the initial luminance of the light-emitting element 9 is 3000 cd/m ² , and the current density is constant. A test was performed. 44 shows the change in luminance according to the driving time when the initial luminance is 100%.

As shown in FIG. 44 , it took about 2300 hours for the luminance of the light emitting element 8 to decrease to 90% of the initial luminance, and about 6000 hours for the luminance of the light emitting element 9 to decrease to 90% of the initial luminance. These results indicate that the light emitting device according to one embodiment of the present invention consumes significantly less power, has little deterioration in luminance, and has high reliability sufficient for practical use.

(Example 4)

In this embodiment, a light emitting device of 254 ppi using a color filter method was actually fabricated. 37 is a photograph of the manufactured light emitting device. In each pixel, red, yellow, green, and blue sub-pixels each having a size of 50 μm×50 μm are arranged in a 2×2 matrix. Fig. 38 shows a comparison between the power consumption of the light emitting device of this embodiment when displaying a still image and the power consumption of the light emitting device of the comparative example using a white color filter method using red, green, and blue sub-pixels. The power consumption of the panel unit displaying a still image was calculated at a peak luminance of 300 cd/m ² .

It is clear from Fig. 38 that the power consumption of the light emitting device of this example is lower than that of the light emitting device of the comparative example. The reduction in power consumption of the present invention is particularly remarkable when displaying an image in which the white display area occupies a large area. Power consumption is the highest when displaying an image in which the white display area occupies a large area, and the higher the ratio of the black display area, the lower the power consumption per unit area in each panel. This is because in liquid crystal displays the backlight needs to be kept on, while OLEDs do not emit light when displaying black.

(Reference example)

In this reference example, the organic compound N , N' -(pyrene-1,6-diyl)bis[(6, N -diphenylbenzo[ b ]naphtho[1,2- d ]furan) used in Examples A method for synthesizing -8-amine] (abbreviation: 1,6BnfAPrn-03) will be described. In addition, the structure of 1,6BnfAPrn-03 is shown below.

<Step 1: Synthesis of 6-iodobenzo[ b ]naphtho[1,2- d ]furan>

In a 500 mL three-neck flask, 8.5 g (39 mmol) of benzo[ b ]naphtho[1,2- d ]furan was put, and the air in the flask was replaced with nitrogen. Then, 195 mL of tetrahydrofuran was added thereto. The solution was cooled to -75°C. Then, 25 mL (40 mmol) of n -butyllithium (1.59 mol/L n -hexane solution) was added dropwise to this solution. After dropping, the resulting solution was stirred at room temperature for 1 hour.

After a certain period of time, the resulting solution was cooled to -75°C. And the solution which melt|dissolved 10 g (40 mmol) of iodine in 40 mL of THF was dripped at this solution. After dropping, the resulting solution was stirred for 17 hours while returning the temperature to room temperature. After a predetermined time, an aqueous solution of sodium thiosulfate was added to the mixture, and the resulting mixture was stirred for 1 hour. Then, the organic layer of the mixture was washed with water and dried using magnesium sulfate. After drying, the mixture was gravity filtered to obtain a solution. The resulting solution was filtered by suction filtration through Celite (Wako Pure Chemical Industries, Ltd., catalog number: 531-16855) and Florisil (Wako Pure Chemical Industries, Ltd., catalog number: 540-00135). got the liquid. The resulting filtrate was concentrated to obtain a solid. The resulting solid was recrystallized from toluene to obtain 6.0 g (18 mmol) of white powder as the target material in a yield of 45%. The synthesis scheme of step 1 is shown below.

<Step 2: Synthesis of 6-phenylbenzo[ b ]naphtho[1,2- d ]furan>

In a 200 mL three-necked flask, 6.0 g (18 mmol) of 6-iodobenzo[ b ]naphtho[1,2- d ]furan, 2.4g (19mmol) phenylboronic acid, 70mL toluene, 20mL ethanol, and 22mL of potassium carbonate aqueous solution (2.0 mol/L) was added. The mixture was degassed by stirring while reducing the pressure. After degassing, the air in the flask was substituted with nitrogen, and then 480 mg (0.42 mmol) of tetrakis(triphenylphosphine)palladium (0) was added to the mixture. The resulting mixture was stirred at 90° C. for 12 hours under a stream of nitrogen.

After a predetermined period of time, water was added to the mixture, and the aqueous layer was extracted with toluene. The extracted solution and the organic layer were mixed, and the mixture was washed with water and then dried using magnesium sulfate. The mixture was gravity filtered to obtain a filtrate. The resulting filtrate was concentrated to obtain a solid, and the resulting solid was dissolved in toluene. The resulting solution was aspirated through Celite (Cat. No. 531-16855, manufactured by Wako Pure Chemical Industries, Ltd.), Florisil (Cat. No.: 540-00135, manufactured by Wako Pure Chemical Industries, Ltd.), and alumina. Filtration to obtain a filtrate. The resulting filtrate was concentrated to obtain a solid. The resulting solid was recrystallized from toluene to obtain 4.9 g (17 mmol) of a white solid as a target material in a yield of 93%. The synthesis scheme of step 2 is shown below.

<Step 3: Synthesis of 8-iodo-6-phenylbenzo[ b ]naphtho[1,2, d ]furan>

4.9 g (17 mmol) of 6-phenylbenzo[ b ]naphtho[1,2- d ]furan was placed in a 300 mL three-necked flask, and the air in the flask was substituted with nitrogen. Then, 87 mL of THF was added thereto. The resulting solution was cooled to -75°C. Then, 11 mL (18 mmol) of n -butyl lithium (1.59 mol/L n -hexane solution) was added dropwise to this solution. After dropping, the resulting solution was stirred at room temperature for 1 hour. After a certain period of time, the resulting solution was cooled to -75°C. And the solution which melt|dissolved 4.6 g (18 mmol) of iodine in 18 mL of THF was dripped at the resulting solution.

The resulting solution was stirred for 17 hours while returning the temperature to room temperature. After a predetermined time, an aqueous solution of sodium thiosulfate was added to the mixture, and the resulting mixture was stirred for 1 hour. Then, the organic layer of the mixture was washed with water and dried using magnesium sulfate. The mixture was naturally filtered to obtain a solution. The resulting solution was purified through Celite (Wako Pure Chemical Industries, Ltd., catalog number: 531-16855), Florisil (Wako Pure Chemical Industries, Ltd., catalog number: 540-00135), and alumina. The filtrate was obtained by suction filtration. The resulting filtrate was concentrated to obtain a solid. The resulting solid was recrystallized from toluene to obtain 3.7 g (8.8 mmol) of a white solid as a target material in a yield of 53%. The synthesis scheme of step 3 is shown below.

<Step 4: Synthesis of 1,6BnfAPrn-03>

In a 100 mL three-necked flask, 0.71 g (2.0 mmol) of 1,6-dibromopyrene, 1.0 g (10.4 mmol) of sodium- tert -butoxide, 10 mL of toluene, 0.36 mL (4.0 mmol) of aniline, and 0.3 mL of tri( tert -butyl)phosphine (10wt% hexane solution) was added, and the air in the flask was substituted with nitrogen. To this mixture, 50 mg (85 μmol) of bis(dibenzylideneacetone)palladium (0) was added, and the resulting mixture was stirred at 80° C. for 2 hours.

After a predetermined time, 1.7 g (4.0 mmol) of 8-iodo-6-phenylbenzo [ b ] naphtho [1,2, d ] furan in the resulting mixture, 180 mg (0.44 mmol) of 2-dicyclohexyl Phosphino-2',6'-dimethoxybiphenyl (abbreviation: S-Phos), and 50 mg (85 μmol) of bis(dibenzylideneacetone)palladium (0) were added, and the resulting mixture was mixed with 100 The mixture was stirred at ℃ for 15 hours. After a predetermined time, the resulting mixture was filtered through Celite (Wako Pure Chemical Industries, Ltd., catalog number: 531-16855) to obtain a filtrate. The resulting filtrate was concentrated to obtain a solid. The resulting solid was washed with ethanol and recrystallized from toluene to obtain 1.38 g (1.4 mmol) of a yellow solid as the target material in a yield of 71%.

By the train sublimation method, 1.37 mg (1.4 mmol) of the resulting yellow solid was purified by sublimation. Purification by sublimation was performed by heating a yellow solid at 370°C under an argon flow rate of 10 mL/min and a pressure of 2.3 Pa. As a result of purification by sublimation, 0.68 g (0.70 mmol) of a yellow solid was obtained in a yield of 50%. The synthesis scheme of step 4 is shown below.

The results of analysis by nuclear magnetic resonance spectroscopy ( ¹ H-NMR) of the yellow solid obtained in step 4 are described below. This result shows that 1,6BnfAPrn-03 was obtained.

¹ H NMR (dichloromethane-d2, 500 MHz): δ = 6.88 (t, J =7.7 Hz, 4H), 7.03-7.06 (m, 6H), 7.11 (t, J =7.5 Hz, 2H), 7.13 (d, J =8.0Hz, 2H), 7.28-7.32(m, 8H), 7.37(t, J =8.0Hz, 2H), 7.59(t, J =7.2Hz, 2H), 7.75(t, J = 7.7 Hz, 2H), 7.84 (d, J =9.0 Hz, 2H), 7.88 (d, J =8.0 Hz, 2H), 8.01 (s, 2H), 8.07 (d, J =8.0 Hz, 4H), 8.14 (d, J =9.0 Hz, 2H), 8.21 (d, J =8.0 Hz, 2H), 8.69 (d, J =8.5 Hz, 2H).

101: first electrode, 102: second electrode, 103a: EL layer, 103b: EL layer, 104a: hole injection layer, 104b: hole injection layer, 105a: hole transport layer, 105b: hole transport layer, 106: light emitting layer, 106a: Light emitting layer, 106b: light emitting layer, 107a: electron transport layer, 107b: electron transport layer, 108a: electron injection layer, 108b: electron injection layer, 109: charge generation layer, 113: first light emitting layer, 114: second light emitting layer, 121: guest material (fluorescent material), 122: host material, 131: guest material (phosphorescent material), 132: first organic compound, 133: second organic compound, 134: exciplex, 501: substrate, 502: FET, 503: first electrode, 504 partition, 505 EL layer, 506R light-emitting region, 506G light-emitting region, 506B light-emitting region, 506W: light-emitting region, 506Y: light-emitting region, 507R: light-emitting element, 507G: light-emitting element, 507B: light-emitting element , 507W: light-emitting element, 507Y: light-emitting element, 508R: colored layer, 508G: colored layer, 508B: colored layer, 508Y: colored layer, 509: black layer (black matrix), 510: second electrode, 511: sealing substrate , 601 element substrate, 602 pixel portion, 603 driver circuit portion (source line driver circuit), 604a driver circuit portion (gate line driver circuit), 604b driver circuit portion (gate line driver circuit), 605 sealant, 606: Sealing substrate, 607 wiring, 608 flexible printed circuit (FPC), 609 FET, 610 FET, 611 switching FET, 612 current control FET, 613 first electrode (anode), 614 insulator, 615: EL layer, 616: second electrode (cathode), 617: light emitting element, 618: space, 1100: substrate, 1102B: first electrode, 1102G: first electrode, 1102Y: first electrode, 1102R: first electrode, 1103d : blue light emitting layer, 1103e: hole injection layer and hole transport Layer, 1103f: yellow light emitting layer, 1103h: electron transport layer and electron injection layer, 1104: second electrode, 1105: black matrix, 1106B: color filter, 1106G: color filter, 1106Y: color filter, 1106R: color filter, 1101: sealing Substrate, 2000: touch panel, 2001: touch panel, 2501: display unit, 2502R: pixel, 2502t: transistor, 2503c: capacitor, 2503g: scan line driver circuit, 2503t: transistor, 2509: FPC, 2510: substrate, 2511: wiring, 2519: terminal, 2521: insulating layer, 2528: partition, 2550R: light emitting element, 2560: sealing layer, 2567BM: light blocking layer, 2567p: antireflection layer, 2567R: colored layer, 2570: substrate, 2580R: light emitting module, 2590: substrate , 2591 electrode, 2592 electrode, 2593 insulating layer, 2594 wiring, 2595 touch sensor, 2597 adhesive layer, 2598 wiring, 2599 connection layer, 2601 pulse voltage output circuit, 2602 current detection circuit, 2603 : capacitor, 2611: transistor, 2612: transistor, 2613: transistor, 2621: electrode, 2622: electrode, 7100: television device, 7101: housing, 7103: display unit, 7105: stand, 7107: display unit, 7109: operation key, 7110 : remote control, 7201 main body, 7202 housing, 7203 display unit, 7204 keyboard, 7205 external connection port, 7206 pointing device, 7302 housing, 7304 display panel, 7305 time icon, 7306 other icon , 7311: operation button, 7312: operation button, 7313: connection terminal, 7321: band, 7322: clasp, 7400: mobile phone, 7401: housing, 7402: display, 7403: operation button, 7404: external connection, 7405: speaker, 7406: microphone, 7407: camera, 7500(1): housing, 7500(2): housing , 7501(1): display unit, 7501(2): display unit, 7502(1): display unit, 7502(2): display unit, 8001: lighting device, 8002: lighting device, 8003: lighting device, 8004: lighting device, 9310 : portable information terminal, 9311: display panel, 9312: display area, 9313: hinge, and 9315: housing
This application is a Japanese patent application with serial number 2014-162532 filed with the Japan Patent Office on August 8, 2014, a Japanese patent application with serial number 2014-162576 filed with the Japan Patent Office on August 8, 2014, 11, 2014 Based on the Japanese Patent Application of Serial No. 2014-241188, filed with the Japan Patent Office on March 28, and the Japanese Patent Application of Serial No. 2015-131156, filed with the Japan Patent Office on June 30, 2015, the entire contents of which are incorporated herein by reference. incorporated by this reference.

Claims (13)

A bottom light emitting device comprising:
a first light emitting device emitting blue light;
a second light emitting element emitting green light;
a third light emitting element emitting red light; and
a fourth light emitting device,
The first to fourth light emitting devices include a first EL layer and a second EL layer having the same structure with a charge generating layer interposed therebetween,
The first EL layer includes a fluorescent material emitting blue light,
and the second EL layer includes a phosphorescent material emitting yellow light.
A bottom light emitting device comprising:
a first light emitting device emitting blue light;
a second light emitting element emitting green light;
a third light emitting element emitting red light; and
a fourth light emitting device,
The first light emitting device includes a first EL layer and a second EL layer having a charge generation layer therebetween,
The second to fourth light emitting devices include the first EL layer and the second EL layer with the charge generation layer interposed therebetween,
The first EL layer includes a first light emitting layer emitting blue light,
and the second EL layer includes a second light emitting layer that emits yellow light.
A bottom light emitting device comprising:
a plurality of pixels;
One of the plurality of pixels,
a first EL layer emitting one of blue light and yellow light;
a second EL layer emitting the other of blue light and yellow light; and
a charge generating layer between the first EL layer and the second EL layer;
The first light emitting device including the first EL layer, the charge generating layer and the second EL layer emits blue light,
a second light emitting device including the first EL layer, the charge generating layer and the second EL layer emits green light;

The third light emitting device including the first EL layer, the charge generating layer and the second EL layer emits red light,
and a fourth light emitting element comprising the first EL layer, the charge generating layer and the second EL layer emits a color different from that of the first to third light emitting elements.
4. The method according to any one of claims 1 to 3,
The peak wavelength of the blue light emitted from the first light emitting device is 400 nm or more and 480 nm or less,
The peak wavelength of the green light emitted from the second light emitting device is 500 nm or more and 560 nm or less,
and a peak wavelength of the red light emitted from the third light emitting element is 580 nm or more and 680 nm or less.
4. The method according to any one of claims 1 to 3,
and the first light emitting element overlaps a transistor electrically connected to an electrode of the first light emitting element.
4. The method according to any one of claims 1 to 3,
The fourth light emitting device emits yellow light,
The peak wavelength of the yellow light is 555 nm or more and 590 nm or less.
The method of claim 1,
wherein the fluorescent material has a pyrene skeleton having two benzo[ b ]naphtho[1,2- d ]furanylamine skeletons.
4. The method according to claim 2 or 3,
wherein the fluorescent material of the first EL layer has a pyrene skeleton having two benzo[ b ]naphtho[1,2- d ]furanylamine skeletons.
8. The method of claim 7,
In the pyrene skeleton, the two benzo[ b ]naphtho[1,2- d ]furanylamine skeletons are bonded to the 1-position and the 6-position.
9. The method of claim 8,
In the pyrene skeleton, the two benzo[ b ]naphtho[1,2- d ]furanylamine skeletons are bonded to the 1-position and the 6-position.
The method of claim 1,
wherein the fluorescent substance has an aromatic diamine skeleton or a pyrenediamine skeleton.
4. The method according to claim 2 or 3,
and the fluorescent substance of the first EL layer has an aromatic diamine skeleton or a pyrenediamine skeleton.
3. The method of claim 1 or 2,
The organic compounds of any one of the first EL layer and the second EL layer form an exciplex.

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